Ultimate Visual Dictionary (DK)

UNGULATES


EXAMPLES OF
UNGULATES





MALE RED DEER BACTRIAN CAMEL
(Cervus elephas) (Camelus ferus)
An even-toed ungulate An even-toed ungulate
(order Artiodactyla) (order Artiodactyla)
EXTERNAL FEATURES Mane
OF A HORSE Poll
GIRAFFE
Crest
(Giraffa camelopardalis)
Ear
An even-toed ungulate
(order Artiodactyla)
Forelock
Withers Forehead
Eye

Muzzle

Nose
Nostril BLACK RHINOCEROS
Cheek
(Diceros bicornis)
An odd-toed ungulate
(order Perissodactyla)
Mouth
Neck Chin
groove
Shoulder Orbit
SKELETON OF A HORSE
Atlas Skull
Lumbar vertebrae
Breast
Thoracic vertebrae Axis
Sacrum
Caudal
vertebrae

Pelvis
Cervical
Elbow Forearm
vertebrae
Femur Scapula
Mandible
Fibula Sternum
Knee Tibia Patella Humerus
Calcaneum Rib Radius
Tarsals
Cannon bone 2nd metatarsal Ulna Carpals
4th metatarsal 3rd metacarpal
3rd metatarsal (cannon bone)
Fetlock
Phalanges of 3rd digit
Phalanges of
Pastern
3rd digit


199

ANIMALS

Elephants DIFFERENCES BETWEEN
AFRICAN AND ASIAN ELEPHANTS
Flat Concave
THE TWO SPECIES OF elephant—African forehead back
and Asian—are the only members of the
Very large
mammalian order Proboscidea. The ears
bigger African elephant is the largest
land animal: a fully grown male may
be up to 13 ft (4 m) tall and weigh nearly
8 tons (7 metric tons). A fully grown male
Asian elephant may be 11 ft (3.3 m) tall 2 “lips” at
and weigh 6 tons (5.4 metric tons). The the end of
the trunk
trunk—an extension of the  nose and
upper lip—is the elephant’s other most
4 toenails AFRICAN ELEPHANT 3 toenails
obvious feature. It is used for (Loxodonta africana)
manipulating and lifting, feeding, Arched
Twin-domed
drinking and spraying water, smelling, forehead back
touching, and producing trumpeting
Smaller ears
sounds. Other characteristic features
include a pair of tusks, used for defense
and for crushing vegetation; thick,
pillarlike legs and broad feet to support
the massive body; and large ear flaps that
1 “lip” at
act as radiators to keep the elephant cool. the end of
the trunk
5 toenails 4 toenails
ASIAN ELEPHANT
(Elephas maximus)
INTERNAL ANATOMY OF
A FEMALE ELEPHANT Duodenum Rump
Spinal cord Heart Stomach Kidney Ureter
Uterus
Brain Rectum
Bladder
Nasal cavity
Anal flap
Buccal cavity
Anus
Mouth Vagina

Tongue Epiglottis
Hind leg
Tusk Esophagus
Small
Trachea intestine
Spleen
Lung
Nasal Vulva
passage Diaphragm



Toenail
Nostril


200

ELEPHANTS

EXTERNAL FEATURES OF A FEMALE AFRICAN
ELEPHANT (TUSKS REMOVED)


Flat forehead



Eye


Pinna (ear flap)








SKULL OF AN
ASIAN ELEPHANT
Orbit Cranium
Maxilla
Jugal
Premaxilla bar
Tusk (upper incisor) Upper
molars


Lower molars
Annulus (ring) Mandible
of trunk
SKELETON OF AN AFRICAN ELEPHANT
(TUSKS REMOVED)
Cervical
vertebrae Thoracolumbar
vertebrae
Skull
Sacrum

Belly
Caudal
Foreleg Mandible vertebrae
Scapula
Trunk
Pelvis
(proboscis) Sternum
Rib Femur
Upper “lip” Humerus
of trunk Patella
Ulna
Radius
Lower “lip” Tibia
of trunk
Carpals
Fibula
Metacarpals
Tarsals
Phalanx
Phalanx
Metatarsals
201

ANIMALS

Primates INTERNAL ANATOMY OF
A FEMALE CHIMPANZEE
THE MAMMALIAN ORDER PRIMATES consists of monkeys,
apes, and their relatives (including humans). There are two Buccal Brain
cavity
suborders of primates: Prosimii, the primitive primates, which
Nasal cavity
include lemurs, tarsiers, and lorises; and Anthropoidea, the Tongue
advanced primates, which include monkeys, apes, and Spinal cord
humans. The anthropoids are divided into New World Trachea Esophagus
monkeys, Old World monkeys, and hominids. New
World monkeys typically have wide-apart nostrils that Lung Heart
open to the side; and long tails, which are prehensile Diaphragm
(grasping) in some species. This group of monkeys Liver
lives in South America, and includes marmosets, Stomach
tamarins, and howler monkeys. Old World monkeys
Pancreas Spleen
typically have close-set nostrils that open forward
Small Large
or downward; and non-prehensile tails. This group
intestine intestine
of monkeys lives in Africa and Asia, and includes
langurs, mandrills, macaques, and baboons. Hominids Cecum Rectum
typically have large brains, and no tail. This group
Appendix Bladder
includes the apes—chimpanzees, gibbons, gorillas,
and orangutans—and humans. Ovary Urethra
Uterus
SKELETON OF A
RHESUS MONKEY Skull
Vagina
Orbit
Cervical
vertebrae
Mandible
Thoracic
vertebrae
Clavicle
Scapula
SKULL OF A CHIMPANZEE
Rib
Temporal bone
Lumbar Humerus
vertebrae Suture Frontal bone
Parietal bone Supraorbital
ridge
Femur Radius
Orbit
Sacrum Ulna
Maxilla
Occipital Premaxilla
bone
Carpals
Patella Tibia
Metacarpals Auditory
Fibula meatus
Incisor
Pelvis Zygomatic tooth
arch
Phalanges
Canine
Tarsals
Caudal Mandible Molar Premolar tooth
vertebrae Metatarsals Phalanges tooth tooth
202

PRIMATES



EXAMPLES OF PRIMATES







RING-TAILED LEMUR MALE RED HOWLER MONKEY MALE MANDRILL CHIMPANZEE
(Lemur catta) (Alouatta seniculus) (Mandrillus sphinx) (Pan troglodytes)
A prosimian A New World monkey An Old World monkey An ape
EXTERNAL FEATURES OF
A YOUNG GORILLA


GOLDEN LION TAMARIN
(Leontopithecus rosalia)
Pinna (ear flap) A New World monkey



Shoulder
Brow ridge
Eye



Nostril

Mouth



Upper arm



Thigh

Forearm Chest


Knee
Elbow

Lower leg




Hand
Foot
Toe
Finger
Toenail


203

ANIMALS

Dolphins, whales,


and seals Rostrum (beak)
Forehead


DOLPHINS, WHALES, AND SEALS belong
to two orders of mammal adapted to living
Mouth
in water. Dolphins and whales make up the
order Cetacea. Typical cetacean features include
a streamlined, fishlike shape; forelimbs in the form Gape
(lower jaw)
of flippers; no visible hind limbs; a horizontally flattened Eye
tail; and thick blubber under the skin. There are two groups
of cetaceans: toothed whales, including sperm whales, white whales,
beaked whales, dolphins, and porpoises; and the larger whalebone (baleen)
whales, including rorquals, gray whales, and right whales. The blue whale—a
rorqual—is the largest living animal: an adult may be up to 100 ft (30 m) long
and weigh 145 tons (130 metric tons). Seals and their relatives—sea lions and
Flipper
walruses—make up the order Pinnipedia. Characteristically, they have a
streamlined, torpedo-shaped body; forelimbs and hind limbs modified as Belly
flippers; thick blubber; and no external ears.
5 digits
EXTERNAL FEATURES OF A SEAL
Auditory
meatus Mouth
Hind flipper
Gape (lower jaw)
Eye
SKELETON OF A SEAL Skull
Nostril
Vibrissa Thoracic Cervical
(whisker)
vertebrae vertebrae
Mouth
5 digits
Lumbar
Front flipper vertebrae
Scapula
Mandible
Sacrum
Caudal Humerus
vertebrae
Ulna
Femur
Radius
Pelvis Rib Sternum
Carpals
Tibia
Phalanges Metacarpals
Fibula
Phalanges
Tarsals


Metatarsals

204

DOLPHINS, WHALES, AND SEALS
EXAMPLES OF CETACEANS

EXTERNAL FEATURES
OF A DOLPHIN



Dorsal fin
BLUE WHALE
(Balaenoptera musculus)










SPERM WHALE
(Physeter catodon)




Tail
MALE BAIRD’S BEAKED WHALE
(Berardius bairdi)









MALE KILLER WHALE
(Orcinus orca)



Tail fluke
MALE NARWHAL
(Monodon monoceros)
INTERNAL ANATOMY OF
A MALE DOLPHIN
Spinal cord Stomach
Kidney
Blowhole (nostril) Brain Aorta
Intestine
Nasal plug Bladder
Melon


Buccal cavity
Anus
Tongue Rectum
Esophagus Liver Penis
Trachea Lung Testis
Heart Urinogenital opening

205

ANIMALS

Marsupials and Skull

SKELETON OF A
KANGAROO
Monotremes
Cervical
Mandible vertebrae
MARSUPIALS AND MONOTREMES are two orders of
mammal that differ from other mammalian groups Scapula
in the ways that their young develop. The order Clavicle
Marsupalia, the pouched mammals, is made up
of kangaroos and their relatives. Typically, Humerus
Thoracic
marsupials give birth to their young at a Sternum vertebrae
very early stage of development. The
young then crawls to the mother’s Radius
pouch (which is on the outside of
her abdomen), where it attaches
itself to a nipple and remains until
Ulna
fully developed. Most marsupials live in
Australia, although the opossums—which Lumbar
vertebrae
are classified as marsupials despite not Carpals
having a pouch—live in the Americas. Metacarpals
The order Monotremata is made up of
Phalanges Rib
the platypus and its relatives (the echidnas,
or spiny anteaters). The monotremes are Femur Sacrum
primitive mammals that lay eggs, which the
mother incubates. The monotremes are found Caudal
only in Australia and New Guinea. vertebrae


SKELETON OF A Skull
PLATYPUS
Orbit
Fibula
1st cervical
vertebra Scapula Tibia Pelvis


Phalanges
Ulna Metacarpals
Carpals
Radius
Humerus 1st thoracic vertebra
Rib

Femur 1st lumbar Tail
vertebra
Tarsals
Tarsals
Fibula Metatarsals
Metatarsals
Phalanges
Phalanges
Tibia Patella
Pelvis 1st caudal vertebra


206

EXAMPLES OF MARSUPIALS Pinna
AND MONOTREMES (ear flap)
EXTERNAL FEATURES
OF A KANGAROO Ear


Eye



Nostril

KOALA DUCK-BILLED PLATYPUS Mouth
(Phascolarctos cinereus) (Ornithorhynchus anatinus)
A marsupial A monotreme









TASMANIAN DEVIL
(Sarcophilus harrisii)
A marsupial




Forelimb



VIRGINIA OPOSSUM
(Didelphis virginiana)
A marsupial
Knee
Thigh
Hip
Claw
5 digits




3 digits

Hind limb



Claw
Hip Lower leg






Foot
207



THE



HUMAN BODY



BODY FEATURES ................................................. 210
HEAD ................................................................. 212
BODY ORGANS .................................................... 214
BODY CELLS ....................................................... 216
SKELETON .......................................................... 218
SKULL ................................................................ 220
SPINE .................................................................. 222
BONES AND JOINTS ............................................. 224
MUSCLES 1 ......................................................... 226
MUSCLES 2 ......................................................... 228
HANDS ............................................................... 230
FEET .................................................................. 232
SKIN AND HAIR .................................................. 234
BRAIN ................................................................. 236
NERVOUS SYSTEM ............................................... 238
EYE .................................................................... 240
EAR .................................................................... 242
NOSE, MOUTH, AND THROAT .............................. 244
TEETH ................................................................ 246
DIGESTIVE SYSTEM ............................................ 248
HEART ................................................................ 250
CIRCULATORY SYSTEM ........................................ 252
RESPIRATORY SYSTEM ........................................ 254
URINARY SYSTEM ............................................... 256
REPRODUCTIVE SYSTEM ..................................... 258
DEVELOPMENT OF A BABY .................................. 260

THE HUMAN BODY
Body features BACK VIEWS OF
MALE AND FEMALE


ALTHOUGH THERE IS enormous Ear
variation between the external
appearances of humans, all bodies
Nape of neck
contain the same basic features.
The outward form of the
human body depends on the Back Shoulder
size of the skeleton, the shape
of the muscles, the thickness
Scapula
of the fat layer beneath (shoulderblade)
the skin, the elasticity or
sagginess of the skin, and
the person’s age and sex. Upper arm
Males tend to be taller than
females, with broader
Elbow
shoulders, more body hair,
and a different pattern of Loin
fat deposits under the skin; Waist
the female body tends to
be less muscular and
Forearm
has a shallower and
wider pelvis to allow Natal
cleft
for childbirth.
Arm
Buttock
Hand



Gluteal fold




Popliteal fossa


Leg


Calf



Foot



Heel






210

BODY FEATURES
FRONT VIEWS OF
MALE AND FEMALE
Forehead
Eye Head
Face Nose
Mouth
Chin

Axilla
(armpit)
Neck
Thorax
(chest) Clavicle (collar bone)

Abdomen Suprasternal notch


Breast
Nipple


Cubital fossa
Umbilicus
Hip (navel)
Groin
Penis Wrist

Scrotum
Thumb
Knuckle

Thigh
Finger
Palm

Knee Pudenda





Shin





Toe

Ankle



Instep


211

THE HUMAN BODY
SIDE VIEW OF EXTERNAL FEATURES OF HEAD
Head

Crown
(vertex)
IN A NEWBORN BABY, the head accounts
for one-quarter of the total body length;
by adulthood, the proportion has reduced
to one-eighth. Contained in the head are
the body’s main sense organs: eyes, ears, Forehead
olfactory nerves that detect smells, and the Eyebrow
taste buds of the tongue. Signals from these
Eyelash
organs pass to the body’s great coordination
center: the brain, housed in the protective, Eye
bony dome of the skull. Hair on the head
Nose
insulates against heat loss, and adult males
also grow thick facial hair. The face has Cheek
three important openings: two nostrils Lip
through which air passes, and the mouth,
Mouth
which takes in nourishment and helps form
speech. Although all heads are basically Chin
Ear
similar, differences in the size, shape, and Jaw
color of features produce an infinite variety
Throat
of appearances.

SECTION THROUGH HEAD

Superior sagittal sinus

Cerebrum
Skull Frontal sinus
Sphenoidal sinus
Pineal body Superior concha
Middle concha
Pituitary gland
Inferior concha
Cerebellum Vestibule
Maxilla (upper jaw)
Pons
Hard palate
Medulla oblongata Soft palate
Tongue
Pharynx
Uvula
Cervical vertebra Mandible (lower jaw)
Palatine tonsil
Spinal cord
Epiglottis
Intervertebral disk Trachea
Esophagus

212

HEAD
FRONT VIEW OF EXTERNAL
FEATURES OF HEAD










Frontal
notch
Frontal
bone


Supraorbital
notch
Supraorbital
Glabella margin
Upper
eyelid
Iris
Lateral angle
Pupil of eye
Sclera Infraorbital
(white) margin

Lower
eyelid Zygomatic
arch
Caruncle
Auricle (pinna)
Root of ear
of nose
Alar groove
Dorsum
of nose
Naris (nostril)
Ala
of nose
Philtral ridge
Nasal
septum
Philtrum

Lateral angle of mouth
Vermilion border
of lip

Mentolabial sulcus











213

THE HUMAN BODY

Body organs MAJOR INTERNAL Larynx
STRUCTURES
Thyroid gland
Heart
ALL THE VITAL BODY ORGANS except for
the brain are enclosed within the trunk
or torso (the body apart from the head
and limbs). The trunk contains two
large cavities separated by a muscular
sheet called the diaphragm. The upper
cavity, known as the thorax or chest cavity, contains
the heart and lungs. The lower cavity, called the
abdominal cavity, contains the stomach, intestines,
liver, and pancreas, which all play a role in digesting Right
lung Left
food. Also within the trunk are the kidneys and
lung
bladder, which are part of the urinary system, and
the reproductive organs, which hold the seeds of new Diaphragm Liver
human life. Modern imaging techniques, such as
contrast X-rays and different types of scans, make Stomach
Large
it possible to see and study body organs without the
intestine
need to cut through their protective coverings of skin,
fat, muscle, and bone. Small
intestine
IMAGING THE BODY










SCINTIGRAM OF ANGIOGRAM OF CONTRAST X-RAY OF
HEART CHAMBERS RIGHT LUNG GALLBLADDER


Greater
omentum






DOUBLE CONTRAST ULTRASOUND SCAN ANGIOGRAM OF
X-RAY OF COLON OF TWINS IN UTERUS KIDNEYS










SCINTIGRAM OF ANGIOGRAM OF CT SCAN THROUGH THERMOGRAM OF ANGIOGRAM OF MRI SCAN THROUGH
NERVOUS SYSTEM ARTERIES OF HEAD FEMALE CHEST CHEST REGION ARTERIES OF HEART HEAD AT EYE LEVEL

214

BODY ORGANS
CHEST AND ABDOMINAL Larynx
CAVITIES WITH SOME
ORGANS REMOVED Thyroid gland

Right common carotid artery Trachea
Right jugular vein Superior vena cava
Right Aorta
subclavian
artery
Right
lung
Upper
lobe
Middle
lobe
Lower
lobe
Left lung
Heart Primary bronchus
Left atrium Secondary bronchus
Right atrium Tertiary bronchus
Left ventricle Diaphragm
Right ventricle Esophagus
Right adrenal gland Spleen

Left adrenal gland
Right kidney
Pancreas
Duodenum Left kidney
Left ureter
Right ureter
Abdominal aorta
Inferior vena cava
Common iliac artery
Common iliac vein
Internal iliac artery


Rectum External iliac artery

Colon
External iliac vein
Bladder



Adipose
(fat) tissue



215

THE HUMAN BODY

Body cells Microvillus



EVERYONE IS MADE UP OF BILLIONS OF CELLS, which are the basic structural units
of the body. Bones, muscles, nerves, skin, blood, and all other body tissues are
formed from different types of cells. Each cell has a specific function but
works with other types of cells to perform the enormous number of tasks
needed to sustain life. Most body cells have a similar basic structure.
Each cell has an outer layer (called the cell membrane) and
contains a fluid material (cytoplasm). Within the cytoplasm are
many specialized structures (organelles). The most important
organelle is the nucleus, which contains
vital genetic material and acts
as the cell’s control center.

Adenine

Thymine

Vacuole

Nucleolus

Nuclear
membrane






Cytosine

Guanine




Phosphate/sugar
band








Smooth
endoplasmic
reticulum


THE DOUBLE HELIX
Diagrammatic representation of DNA, which is structured like Secretory vesicle
a spiral ladder. DNA contains all the vital genetic information
and instruction codes necessary for the maintenance and Nucleoplasm
continuation of life.

216

BODY CELLS
GENERALIZED HUMAN CELL TYPES OF CELLS



Cytoplasm

Lysosome


Cell membrane
BONE-FORMING NERVE CELLS IN
CELL SPINAL CORD
Mitochondrial
crista



Nucleus


Rough
endoplasmic
reticulum
SPERM CELLS SECRETORY
IN SEMEN THYROID GLAND
CELLS
Microfilament


Pore of
nuclear membrane


Ribosome
ACID-SECRETING CONNECTIVE TISSUE
STOMACH CELLS CELLS
Centriole


Mitochondrion

Microtubule



MUCUS-SECRETING RED AND TWO
DUODENAL CELLS WHITE BLOOD
Peroxisome
CELLS


Pinocytotic vesicle




Golgi complex (Golgi apparatus;
Golgi body)
FAT CELLS IN EPITHELIAL CELLS
ADIPOSE TISSUE IN CHEEK

217

THE HUMAN BODY

Skeleton Metacarpal

Carpus
THE SKELETON IS A MOBILE FRAMEWORK made up of 206 bones, approximately Ulna
half of which are in the hands and feet. Although individual bones are rigid, Radius
the skeleton as a whole is remarkably flexible and allows the human body a
huge range of movement. The skeleton serves as an anchorage for the skeletal
muscles, and as a protective cage for the body’s internal organs.
Female bones are usually smaller and lighter
than male bones, and the female pelvis
Humerus Wrist joint
is shallower and has a wider cavity.
Elbow joint
Shoulder joint
Hip joint
Rib cage Intervertebral
disk

Sternum
(breast bone)
Costal
cartilage

Coccyx



Sacrum
Pubis
Vertebral
column
(spine)


Ischium



Skull

“True” ribs Ilium
(1st to 7th)

“False” ribs “Floating” ribs
Clavicle (8th to 10th) (11th and 12th)
(collar bone)
Scapula
(shoulderblade)

Humerus Radius Ulna Carpus









218

SKELETON


Distal phalanx
Middle phalanx

Proximal phalanx





Femur Patella Tibia Fibula Tarsus


Proximal phalanx
Middle phalanx

Distal
phalanx






Ankle joint Metatarsal
Knee
joint






Distal phalanx
Patella
Middle phalanx
Proximal phalanx










Femur
Tibia Fibula Tarsus Metatarsal
Proximal phalanx
Metacarpal
Middle phalanx

Distal phalanx






219

THE HUMAN BODY

Skull



THE SKULL is the most complicated bony structure
of the body but every feature serves a purpose. RIGHT SIDE VIEW OF
A FETAL SKULL
Internally, the main hollow chamber of the skull
has three levels that support the brain, with
every bump and hollow corresponding to the Anterior fontanelle
shape of the brain. Underneath and toward Parietal
the back of the skull is a large round hole, the bone Coronal suture
foramen magnum, through which the spinal
cord passes. To the front of this are many smaller openings
through which nerves, arteries, and veins pass to and from the
Frontal
brain. The roof of the skull is formed from four thin, curved bones bone
that are firmly fixed together from the age of about two years. At
the front of the skull are the two orbits, which contain the eyeballs,
Nasal bone
and a central hole for the airway of the nose. The jaw bone hinges
on either side at ear level.

Mental
Lambdoid symphysis
RIGHT SIDE VIEW OF SKULL suture
Frontal bone
Coronal suture Occipital bone
Greater wing of
sphenoid bone Frontozygomatic Sphenoidal
suture Mastoid fontanelle
Parietal bone fontanelle External
Supraorbital margin auditory
Squamous meatus
suture Orbital
cavity VIEW OF SKULL FROM BELOW
External occipital crest
Nasal bone
Foramen magnum
Anterior nasal spine
Maxilla Occipital condyle
Lambdoid (upper jaw)
suture
Carotid canal
Occipital bone Mandible
(lower
jaw) Mastoid process
Temporal bone
External Pharyngeal
auditory meatus Styloid process tubercle
Condyle
Mastoid process Zygomatic Zygomatic arch Pterygoid plate
Coronoid bone
process
Posterior border Pterygoid hamulus
Mental foramen of vomer
Greater palatine
Concha foramen

Mandible (lower jaw) Posterior nasal aperture

220

SKULL


FRONT VIEW OF SKULL


Nasion Frontal bone
Glabella

Nasal bone
Parietal bone




Temporal bone



Lesser wing of Supraorbital
sphenoid bone foramen


Greater wing of
sphenoid bone Supraorbital
margin

Frontal process Superior
of maxilla orbital
fissure

Lacrimal bone
Nasal septum
Zygomatic
bone

Middle nasal concha Inferior orbital
fissure

Infraorbital
Inferior nasal concha margin

Infraorbital foramen
Vomer
Maxilla
(upper jaw)



Anterior nasal spine Mandible
(lower jaw)


Mental foramen
Mental
protuberance




221

THE HUMAN BODY

Spine SPINE DIVIDED INTO FRONT
VERTEBRAL SECTIONS
Cervical vertebrae
THE SPINE (OR VERTEBRAL COLUMN) has two main functions:
it serves as a protective surrounding for the delicate spinal
cord and forms the supporting back bone of the skeleton.
The spine consists of 24 separate differently shaped bones
Thoracic vertebrae
(vertebrae) with a curved, triangular bone (the sacrum) at
the bottom. The sacrum is made up of fused vertebrae; at its
lower end is a small tail-like structure made up of tiny bones
collectively called the coccyx. Between each pair of vertebrae
is a disk of cartilage that cushions the bones during movement.
The top two vertebrae differ in appearance from the others and Lumbar vertebrae
work as a pair: the first, called the atlas, rotates around a stout
vertical peg on the second, the axis. This arrangement allows
the skull to move freely up and down, and from side to side.
Sacral vertebrae
Coccygeal vertebrae
TYPES OF VERTEBRAE (VIEWED FROM ABOVE)
ATLAS AXIS CERVICAL VERTEBRA
Lateral mass with
superior articular facet
Anterior Superior
arch Posterior Vertebral foramen Body articular
arch Facet process
Anterior
tubercle Posterior Dens Spinous Anterior Spinous
tubercle process tubercle process
Vertebral
foramen Lamina Vertebral
Transverse foramen
Transverse foramen Posterior
process Transverse process tubercle Transverse
and foramen foramen

Skull

SKULL AND SPINE







Thoracic vertebrae
Cervical vertebrae
7th
1st 6th
2nd 3rd 4th 5th 6th 7th 1st 2nd 3rd 4th 5th









Atlas Axis

222

SPINE
RIGHT SIDE BACK CERVICAL VERTEBRA AND
SECTION OF SPINAL CORD Superior articular
process

Vertebral artery Anterior horn
Vertebral body
Posterior horn
Anterior median Spinous process of
fissure cervical vertebra
Spinal cord Posterior column

Anterior root Dura mater
Lateral column
Spinal ganglion
Posterior root
Anterior branch
of spinal nerve Posterior branch
of spinal nerve
SACRUM COCCYX
Ala Lateral part
of sacrum
THORACIC VERTEBRA LUMBAR VERTEBRA Coccygeal
Superior articular cornu
process Pedicle Superior Transverse
Vertebral articular process
Body foramen Body process
and facet
Spinous Spinous
process process
Lamina Lamina

Costal Inferior
facet Vertebral articular Facet for
Transverse foramen process coccyx
process
Transverse Site of fusion of
process vertebral bodies
Sacral
promontory Sacral foramen
Auricular
surface
Lumbar vertebrae
2nd 3rd
1st
12th 4th
11th
5th
10th
9th Intervertebral disk
8th


Sacrum



Coccyx





223

THE HUMAN BODY

Bones and LIGAMENTS SURROUNDING HIP JOINT


joints Iliac Iliac fossa
crest

Pubofemoral
BONES FORM the body’s hard, strong ligament
skeletal framework. Each bone has a
hard, compact exterior surrounding Iliac
a spongy, lighter interior. The long spine
bones of the arms and legs, such as
the femur (thigh bone), have a central
cavity containing bone marrow. Bones Obturator
canal
are composed chiefly of calcium,
Greater trochanter
phosphorus, and a fibrous substance of femur Superior
known as collagen. Bones meet at joints, ramus of
pubis
which are of several different types. For Iliofemoral
example, the hip is a ball-and-socket ligament
joint that allows the femur a wide range
of movement, whereas finger joints are Body
simple hinge joints that allow only of
Intertrochanteric pubis
bending and straightening. Joints are
line
held in place by bands of tissue called
ligaments. Movement of joints is Lesser trochanter Obturator
of femur membrane
facilitated by the smooth hyaline
cartilage that covers the bone ends
and by the synovial membrane that Ischial tuberosity
lines and lubricates the joint.
Femur
Ischium







SECTION THROUGH LEFT FEMUR

Greater
trochanter
Medullary cavity
Shaft


Cancellous
(spongy) bone


Head
Lesser
trochanter Compact bone
Neck
Fovea

224

BONES AND JOINTS
SECTION THROUGH HIP JOINT SECTION OF
Psoas major muscle Iliacus muscle COMPACT BONE
Iliac crest
External
iliac artery


Hyaline cartilage
of acetabulum Gluteus
minimus muscle
Hyaline cartilage
of head of femur Gluteus
medius muscle
Ligament of
head of femur Acetabular
labrum
Parallel rows of concentric
bony layers make up this
Femoral Articular Head
artery cavity of femur strong material.
Greater BONE MARROW SMEAR
trochanter
of femur
Neck of
femur





Vastus
lateralis
muscle

Composed mainly of red and
white blood cells, marrow fills
Shaft
Pectineus of femur the cavities of bones.
muscle

Adductor Iliacus Vastus SECTION THROUGH LONG BONE
longus muscle muscle medialis muscle

Lateral Osteon Haversian lamella
epicondyle (haversian system)
Outer lamella
Patellar Osteocyte Sharpey’s
surface (bone cell) fiber


Intermediate
lamella



Endosteum
Periosteum
Medial
epicondyle Haversian canal
Adductor tubercle
Lacuna
Volkmann’s vessel

225

THE HUMAN BODY

Muscles 1 SUPERFICIAL SKELETAL MUSCLES
FRONT VIEW


THERE ARE THREE MAIN TYPES OF MUSCLE: skeletal Brachioradialis
muscle (also called voluntary muscle because it can be
Flexors of
consciously controlled); smooth muscle (also called forearm Frontalis
involuntary muscle because it is not under voluntary
control); and the specialized muscle tissue of the heart. Brachialis
Humans have more than 600 skeletal muscles, which Orbicularis oculi
differ in size and shape according to the jobs they do.
Temporalis
Skeletal muscles are attached either directly or indirectly
(via tendons) to bones, and work in opposing pairs (one
muscle in the pair contracts while the other relaxes) to
Sternocleidomastoid
produce body movements as diverse as walking, threading
a needle, and an array of facial expressions. Smooth muscles Trapezius
occur in the walls of internal body organs and perform
actions such as forcing food through the intestines, Pectoralis major
contracting the uterus (womb) in childbirth, and
pumping blood through the blood vessels. Deltoid
Serratus anterior
SOME OTHER MUSCLES Rectus abdominis Biceps brachii
IN THE BODY
Linea alba
Iris External oblique
Pupil Tensor fasciae latae




Iliopsoas
IRIS Pectineus
The muscle fibers contract and
dilate (expand) to alter pupil size.
Adductor longus
Vastus lateralis Rectus femoris
Gracilis
Sartorius
Vastus medialis




TONGUE
Interlacing layers of muscle Gastrocnemius
allow great mobility.
Tibialis anterior








ILEUM
Opposing muscle layers
transport semidigested food.

226

MUSCLES 1
MOVEMENT OF THE FOREARM
Controlled movement of the limbs relies
BACK VIEW on coordinated relaxation and contraction
Extensors Flexors of opposing muscles. To raise the forearm,
of hand of hand the biceps (two-rooted muscle) contracts
and shortens while the triceps (three-
rooted muscle) relaxes; the reverse
occurs when the forearm is lowered.

Temporalis
Triceps in
Triceps resting phase
brachii
Sternocleidomastoid Biceps in
resting phase
Teres minor
Forearm
Trapezius Teres major at rest
Infraspinatus

Rhomboideus major
Deltoid
Latissimus dorsi Triceps
relaxes
Forearm
Biceps half raised
contracts





Triceps fully
Gluteus relaxed
maximus
Biceps fully
contracted
Adductor Forearm
magnus fully raised
Gracilis
Biceps femoris
Semitendinosus Triceps
contracts
Forearm
Biceps half lowered
relaxes



Gastrocnemius
Triceps back in
Soleus resting phase
Biceps back in
Peroneus resting phase Forearm
brevis back at rest








227

THE HUMAN BODY

Muscles 2 MUSCLES OF FACIAL
EXPRESSION
A single expression
is the result of
Myofibril movement of many
SKELETAL MUSCLE FIBER muscles; the main
muscles of expression
are shown in action
below.


FRONTALIS
Sarcomere
Motor
end plate


Nucleus
Synaptic
knob
Sarcoplasmic
reticulum
CORRUGATOR
SUPERCILII

Sarcolemma
Schwann
cell
Motor Endomysium
neuron
Node of
Ranvier

ORBICULARIS ORIS
TYPES OF MUSCLE











CARDIAC MUSCLE SKELETAL MUSCLE SMOOTH MUSCLE ZYGOMATICUS MAJOR
CONTRACTION OF SKELETAL MUSCLE











DEPRESSOR ANGULI
RELAXED STATE CONTRACTED STATE
ORIS
228

MUSCLES 2
MUSCLES OF
HEAD AND NECK

Frontalis



Procerus

Temporalis
Corrugator
supercilii

Orbicularis
oculi
Levator labii
superioris
Zygomaticus
major

Nasalis










Orbicularis oris
Buccinator



Masseter
Risorius
Depressor labii
Levator anguli oris inferioris
Platysma
Mentalis
Depressor anguli oris



Thyrohyoid

Scalenus medius
Sternocleidomastoid
Sternohyoid
Omohyoid
Cricothyroid
Trapezius


229

THE HUMAN BODY
X-RAY OF LEFT HAND
Hands OF A YOUNG CHILD

Area of
ossification
THE HUMAN HAND is an extremely versatile in phalanx
tool, capable of delicate manipulation as well as
powerful gripping actions. The arrangement of
its 27 small bones, moved by 37 skeletal muscles
that are connected to the bones by tendons,
allows a wide range of movements. Our ability
to bring the tips of our thumbs and fingers
together, combined with the extraordinary sensitivity
Area of
of our fingertips due to their rich supply of nerve ossification
endings, makes our hands uniquely dextrous. in metacarpal

Ring Middle Index Area of
finger finger finger ossification
BONES in wrist
OF HAND Epiphysis
Epiphysis
of radius
Little of ulna
finger
Distal Areas of cartilage in the wrist and at the
phalanx ends of the finger bones are the sites of
growth and have still to ossify.

Middle
phalanx




Proximal
phalanx
Distal phalanx
Head of thumb
2nd
metacarpal
3rd
metacarpal Shaft Proximal phalanx
of thumb
4th
metacarpal
Base
5th
metacarpal
1st metacarpal
Hamate
Pisiform
Trapezium
Trapezoid
Capitate
Scaphoid
Triquetral
Lunate
Ulna Radius



230

HANDS
STRUCTURES UNDERLYING SKIN Flexor pollicis
OF PALM OF HAND brevis muscle
Opponens
pollicis
muscle Abductor
pollicis
Adductor pollicis muscle brevis
muscle Flexor
2nd lumbrical muscle retinaculum
Radial
artery









Digital artery Digital nerve





Flexor digitorum tendon
Abductor Ulnar Ulnar
Opponens digiti nerve artery
digiti minimi
minimi muscle Palmaris
muscle longus
EXTERNAL FEATURES OF BACK OF HAND tendon
Distal
interphalangeal joint
Little finger
Proximal
interphalangeal joint
Extensor digitorum
tendon
Ring finger Head of ulna




Middle
finger
Cuticle
Lunule



Index
finger
Distal end
Wrist of radius
Nail Metacarpophalangeal
joint



Thumb



231

THE HUMAN BODY
BONES OF FOOT
Feet

2nd toe Hallux
(big toe)
THE FEET AND TOES are essential elements
in body movement. They bear and propel the 3rd toe
Distal
weight of the body during walking and phalanx of
running, and also help to maintain balance 4th toe hallux
during changes of body position. Each foot 5th
(little) toe
has 26 bones, more than 100 ligaments,
and 33 muscles, some of which are Distal Proximal
phalanx phalanx of
attached to the lower leg. The heel
hallux
pad and the arch of the foot act Middle
as shock absorbers, providing phalanx
a cushion against the jolts that
Proximal
occur with every step. phalanx

1st
metatarsal
2nd
LIGAMENTS OF FOOT metatarsal
Articular 3rd
capsule of metatarsal
Posterior interphalangeal
cuneonavicular joint 4th 1st
ligament metatarsal cuneiform

Plantar 5th
calcaneonavicular metatarsal 2nd
ligament cuneiform

3rd
cuneiform
Articular capsule of
metatarsophalangeal
joint Navicular
Cuboid

Talus
Posterior
tarsometatarsal
ligament
Talonavicular
ligament
Bifurcate
ligament Deltoid
ligament
Fibula Tibia
Calcaneus
Calcanean
(Achilles) Interosseous
tendon ligament





232

FEET
STRUCTURES UNDERLYING SKIN OF FOOT
Calcanean
Flexor hallucis (Achilles)
longus muscle tendon
Flexor digitorum
Extensor hallucis 1st dorsal Medial longus muscle Soleus
longus tendon interosseous muscle malleolus muscle
Tibia
Inferior extensor Tibialis
retinaculum anterior muscle















Tibialis
posterior muscle Fibula
Extensor Lateral
digitorum malleolus Peroneus
longus tendon brevis muscle
Abductor digiti Peroneus brevis tendon
minimi muscle Peroneus
Extensor digitorum longus muscle
brevis muscle
Extensor hallucis
brevis muscle

EXTERNAL FEATURES OF FOOT

Toenail Hallux Interphalangeal Extensor hallucis
(big toe) joint longus tendon Extensor digitorum
longus tendon
Medial malleolus
















2nd toe
3rd toe
4th toe 5th Lateral malleolus
(little) toe



233

THE HUMAN BODY
Skin and hair SECTION OF HAIR
Medulla

SKIN IS THE BODY’S LARGEST ORGAN, a
waterproof barrier that protects the internal
organs against infection, injury, and harmful
sun rays. The skin is also an important
sensory organ and helps to control body
Cortex
temperature. The outer layer of the skin, known as
the epidermis, is coated with keratin, a tough, horny
protein that is also the chief constituent of hair and
nails. Dead cells are shed from the skin’s surface
and are replaced by new cells from the base of the
Melanin
epidermis, the region that also produces the skin
granule
pigment, melanin. The dermis contains most of the
skin’s living structures, and includes nerve endings, Cell
nucleus
blood vessels, elastic fibers, sweat glands that cool
residue
the skin, and sebaceous glands that produce oil to
keep the skin supple. Beneath the dermis lies the Macrofibril
subcutaneous tissue (hypodermis), which is rich in fat
and blood vessels. Hair shafts grow from hair follicles
situated in the dermis and subcutaneous tissue. Hair
grows on every part of the skin apart from the palms
of the hands and soles of the feet.

Cuticle
SECTIONS OF DIFFERENT TYPES OF SKIN


Sebaceous gland Hair Enlarged Thickened
follicle sweat gland epidermis Sweat pore


Meissner’s
corpuscle


Follicle-
rich
dermis




Sweat
gland


Pacinian
corpuscle






SCALP ARMPIT SOLE OF FOOT

234

SKIN AND HAIR
SECTION OF SKIN
Stratum Stratum Sweat Hair Sweat duct
granulosum corneum pore shaft
Stratum Merkel’s disk
spinosum
Stratum
basale
Dermal
papilla Epidermis

Free
nerve
ending
Meissner’s
corpuscle


Vascular
plexus
Nerve Dermis
fiber

Sebaceous
gland

Arrector
pili
muscle
Hair
bulb

Hypodermis
Papilla
Pacinian
corpuscle


Adipose (fat) Ruffini
tissue corpuscle
Sweat Hair
Vein gland follicle
Artery


PHOTOMICROGRAPHS OF SKIN AND HAIR












SECTION OF SKIN SWEAT PORE SKIN HAIR HEAD HAIR
The flaky cells at the skin’s This allows loss of fluid as part Two hairs pushing through the The root and part of the shaft of
surface are shed continuously. of temperature control. outer layer of skin. a hair from the scalp.


235

THE HUMAN BODY

Brain MRI SCAN OF TRANSVERSE
SECTION THROUGH BRAIN


THE BRAIN IS THE MAJOR ORGAN of the central nervous Grey
system and the control center for all the body’s voluntary White matter
matter
and involuntary activities. It is also responsible for the
complexities of thought, memory, emotion, and language.
In adults, this complex organ is a mere 3 lb (1.4 kg) in Skull
weight, containing over 10 billion nerve cells. Three distinct
regions can easily be seen—the brainstem, the cerebellum,
and the large cerebrum. The brainstem controls vital body Scalp
functions, such as breathing and digestion. The cerebellum’s
main functions are the maintenance of posture and the Lateral
ventricle
coordination of body movements. The cerebrum, which
Longitudinal
consists of the right and left cerebral hemispheres joined fissure Coronal
by the corpus callosum, is the site of most conscious and section
Sagittal
intelligent activities. section
SAGITTAL SECTION
THROUGH BRAIN Fornix Cerebrum
Central sulcus




Corpus
Parietal lobe callosum

Parieto-occipital
sulucs Thalamus



Pineal
body



Occipital
lobe Frontal
lobe

Aqueduct Hypothalamus

Cerebellum Optic
chiasma
Pituitary gland
4th ventricle
Mesencephalon
(midbrain)
Pons Brainstem
Spinal cord
Medulla
oblongata

236

BRAIN
SECTION THROUGH SKULL AND BRAIN EXTERNAL ANATOMY OF BRAIN
Epicranial Parietal lobe Parieto-occipital
Scalp aponeurosis sulcus
Precentral gyrus
Arachnoid Pericranium
granulation Postcentral gyrus
Skull
Central sulcus
Lateral Dura mater
lacuna Frontal lobe
Arachnoid
mater
Superior Lateral sulcus
sagittal Pia mater Occipital
sinus lobe
Temporal lobe
Falx Subarachnoid Cerebellum
cerebri space
SPECIFIC ROLES OF
Cerebral AREAS OF CEREBRUM
Gray matter vessel
Cerebrum Skilled Basic Sensation
White matter movements movements
Visual
recognition
CORONAL SECTION THROUGH BRAIN Behavior and
Grey matter emotion
Longitudinal Cerebrum
Corpus fissure White matter
callosum Speech
Caudate Lateral
nucleus ventricle
Vision
Hearing
Fornix Balance
and muscle
coordination
Lentiform
nucleus NERVE CELLS IN BRAIN

Internal
capsule


Thalamus

Crus
cerebri of
midbrain


3rd
ventricle


Pons



Medulla oblongata
Cerebellum The dark cells are Purkinje’s
cells, which are among the
largest nerve cells in the body.

237

THE HUMAN BODY

Nervous CENTRAL AND PERIPHERAL
NERVOUS SYSTEMS
Cranial Cerebrum
nerves
system Cerebellum


Cervical
nerves
THE NERVOUS SYSTEM IS THE BODY’S internal, Brachial
electrochemical, communications network. plexus
Its main parts are the brain, spinal cord, and
nerves. The brain and spinal cord form the
central nervous system (CNS), the body’s
chief controlling and coordinating Spinal
centers. Billions of long neurons, cord
Thoracic
many grouped as nerves, make
nerves
up the peripheral nervous system, transmitting
nerve impulses between the CNS and other
Radial
regions of the body. Each neuron has three
nerve
parts: a cell body, branching dendrites that
Median
receive chemical signals from other neurons, nerve
and a tubelike axon that conveys these
Ulnar
signals as electrical impulses. Lumbar nerve
nerves
Sacral
nerves

Sacral
plexus
SECTION THROUGH SPINAL CORD
Femoral
nerve Pudendal
nerve
Gray matter Central
Spinal canal Posterior root Sciatic
ganglion of spinal nerve nerve
Spinal nerve Cutaneous
nerve
Common
peroneal
nerve


Posterior
tibial nerve
White matter
Superficial
Anterior median fissure Anterior root peroneal
of spinal nerve nerve


Deep
peroneal
nerve



238

NER VOUS SYSTEM
STRUCTURE OF A MOTOR NEURON
Cell body
Nucleus
Schwann Node of
Synaptic cell Ranvier
knob
Axon hillock




Axon
Myelin sheath
Dendrite
Mitochondrion
TYPES OF
Nucleolus NERVE ENDING
Nissl TYPES OF NEURON
body
MULTIPOLAR UNIPOLAR BIPOLAR
STRUCTURE OF Motor end plate Dendrite Dendrite
A SYNAPTIC KNOB

Presynaptic
axon FREE NERVE
ENDING
Microtubule

Neurofilament Axon
Endoplasmic
reticulum
Mitochondrion Axon
Synaptic MEISSNER’S
vesicle Node of CORPUSCLE
Ranvier
Cell Nucleus
Neurotransmitter Presynaptic body
membrane
Schwann
cell
MERKEL’S DISK
Myelin sheath Cell body


Axon

Nucleus Nucleus
Cell body
Dendrite RUFFINI CORPUSCLE
Dendrite

Receptor
PACINIAN
CORPUSCLE

239

THE HUMAN BODY

Eye Lateral
rectus muscle


THE EYE IS THE ORGAN OF SIGHT. The two eyeballs, protected
within bony sockets called orbits and on the outside by the
eyelids, eyebrows, and tear film, are directly connected
to the brain by the optic nerves. Each eye is moved by
six muscles, which are attached around the eyeball.
Light rays entering the eye through the pupil
are focused by the cornea and lens to form
an image on the retina. The retina contains
millions of light-sensitive cells, called
rods and cones, which convert the image
into a pattern of nerve impulses. These
impulses are transmitted along the optic
nerve to the brain. Information from
the two optic nerves is processed
in the brain to produce a
single coordinated image.


Vitreous humor



Macula


Central retinal vein
Central retinal artery
Pia mater
Arachnoid mater
Dura mater
Optic nerve






Area of
optic disk
Retina
Choroid
Sclera


Retinal blood vessel

Medial
rectus muscle

240

EYE
SECTION THROUGH LEFT EYE LACRIMAL (TEAR-PRODUCING) APPARATUS
Lacrimal sac Lacrimal canaliculus Lacrimal gland



Middle
meatus


Middle
nasal
concha




Nasal Lacrimal
septum Inferior Nasolacrimal punctum
nasal concha duct
Iris
OPHTHALMOSCOPIC VIEW
Anterior OF RETINA
chamber
Aqueous Retinal
Posterior humour blood vessel
chamber
Conjunctiva
Optic
Macula disk
Pupil
Cornea

Lens
Sphincter
muscle
The blind spot, where the optic nerve
Dilator leaves the eye, can be clearly seen as a
muscle light circular area toward the center of
the image.
Zonular
ligament
MUSCLES SURROUNDING RIGHT EYE
Sinus venosus
sclerae Medial rectus Superior oblique
Trochlea
Iridocorneal Levator palpebrae
angle superioris Superior
rectus
Ciliary
body

Annular
tendon




Ora Inferior rectus
serrata Lateral rectus
Inferior oblique

241

THE HUMAN BODY

Ear STRUCTURE OF EAR


Temporal bone
THE EAR IS THE ORGAN OF HEARING AND BALANCE. The outer ear
consists of a flap called the auricle or pinna and the auditory canal.
The main functional parts-the middle and inner ears-are enclosed
within the skull. The middle ear consists of three tiny bones,
known as auditory ossicles, and the eustachian tube, which links the
ear to the back of the nose. The inner ear consists of the spiral- Cartilage
shaped cochlea, and also the semicircular canals and the vestibule, of auricle
which are the organs of balance. Sound waves entering the ear
travel through the auditory canal to the tympanic membrane
(eardrum), where they are converted to vibrations that are
transmitted via the ossicles to the cochlea. Here, the vibrations
are converted by millions of microscopic hairs into electrical
nerve signals to be interpreted by the brain.

Upper crux of Auricle
RIGHT AURICLE (PINNA) antihelix (pinna)
Triangular
fossa
Scaphoid fossa
Lower crux
of antihelix
Concha
Helix
Auditory canal

Antihelix

Antitragus Tragus
Intertragic Mastoid
External notch process
auditory Cartilaginous
meatus part of meatus
Lobule
Lobule
OSSICLES OF MIDDLE EAR
INTERNAL STRUCTURE
OF AMPULLA
Membranous Cupula
portion





Osseous
portion
MALLEUS (HAMMER) INCUS (ANVIL) STAPES (STIRRUP) Crista Ampullar
nerve
These three tiny bones connect to form a bridge between the Hair cell
tympanic membrane and the oval window. With a system of of crista
membranes they convey sound vibrations to the inner ear.

242

EAR
LABYRINTH
Vestibular
Utricle nerve
Saccule
Tympanic
Osseous (bony) Common crus canal
part of meatus
Anterior Median
semicircular canal
canal
Tympanic membrane Vestibular
(eardrum) Lateral canal
semicircular
canal
Semicircular canal Cochlea
Ampulla



Vestibulocochlear
nerve Cochlear nerve
Tensor
Cochlea tympani muscle Oval window
Posterior semicircular
canal
SECTION THROUGH COCHLEA
Organ Median
of Corti canal
Vestibular canal

Internal
carotid artery

Vestibular
membrane
Eustachian
tube Spiral
ganglion

Cochlear
nerve
Hair cells

Tympanic canal Basilar
membrane









Styloid process






243

THE HUMAN BODY

Nose, mouth, STRUCTURE OF TONGUE

Median Epiglottis
glossoepiglottic
and throat fold Palatine
tonsil
Sulcus
WITH EVERY BREATH, air passes through the nasal terminalis
cavity down the pharynx (throat), larynx (“voice Palatoglossal
arch
box”), and trachea (windpipe) to the lungs. The nasal Foramen
cavity warms and moistens air, and the tiny layers in cecum Vallate
papilla
its lining protect the airway against damage by foreign
bodies. During swallowing, the tongue moves up and Foliate
back, the larynx rises, the epiglottis closes off the Median papilla
sulcus
entrance to the trachea, and the soft palate separates
Fungiform
the nasal cavity from the pharynx. Saliva, secreted papilla
from three pairs of salivary glands, lubricates food to
Filiform papilla
make swallowing easier; it also begins the chemical
breakdown of food, and helps to produce taste. The
senses of taste and smell are closely linked. Both
depend on the detection of dissolved molecules by Apex
sensory receptors in the olfactory nerve endings of
the nose and in the taste buds of the tongue.
TASTE AREAS ON TONGUE
Lingual
STRUCTURES
nerve
SURROUNDING Tongue
PHARYNX
Styloglossus muscle
Hyoglossus muscle Bitter
Sublingual
gland
Hypoglossal
nerve Mandible
(lower jaw) Sour
Superior
laryngeal Submandibular
nerve gland Salt
Superior Hyoid bone
thyroid
artery Laryngeal prominence
(Adam’s apple)
Sweet
TYPES OF PAPILLAE
Thyrohyoid
muscle
Thyrohyoid
membrane
Cricothyroid
muscle Cricothyroid
ligament

Thyroid gland

Trachea
FILIFORM PAPILLAE FUNGIFORM PAPILLAE VALLATE PAPILLAE

244

NOSE, MOUTH, AND THROAT
SECTION THROUGH NOSE,
MOUTH, AND THROAT

Superior nasal concha
Frontal sinus Sphenoidal sinus


Middle nasal concha

Superior meatus
Inferior nasal concha
Middle meatus
Nasal cavity
Vestibule Soft palate

Inferior meatus
Nasopharynx
Hard palate
Maxilla
(upper jaw)
Incisive canal
Orbicularis oris muscle
Superior
longitudinal muscle Uvula
Incisor Palatine
tonsil
Apex of tongue
Oropharynx
Genioglossus muscle
Epiglottis
Sublingual fold
Lingual
Sublingual salivary gland tonsil
Fibrous septum
Mandible (lower jaw)
Geniohyoid muscle
Myohyoid muscle
Hyoid bone Cricothyroid
ENDOSCOPIC VIEW OF VOCAL CORDS muscle
Laryngeal
Posterior prominence Cervical
part of (Adam’s apple) vertebra
tongue


Thyroid cartilage

Thyroid gland Intervertebral
disk
Esophagus
Trachea
Epiglottis Vocal cord



245

THE HUMAN BODY

Teeth DEVELOPMENT OF TEETH IN A FETUS



THE 20 PRIMARY TEETH (also called deciduous or baby
Fetal skull
teeth) usually begin to erupt when a baby is about six
months old. They start to be replaced by the permanent
teeth when the child is about six years old. By the age of
Primary teeth
20, most adults have a full set of 32 teeth although the
in maxilla
third molars (commonly called wisdom teeth) may never (upper jaw)
erupt. While teeth help people to speak clearly and give
shape to the face, their main function is the chewing of
food. Incisors and canines shear and tear the food into Primary teeth
pieces; premolars and molars crush and grind it further. in mandible
(lower jaw)
Although tooth enamel is the hardest substance in the
body, it tends to be eroded and destroyed by acid FETAL JAWS
produced in the mouth during the breakdown of food. By the sixth week of embryonic development areas of
thickening occur in each jaw; these areas give rise to
tooth buds. By the time the fetus is six months old,
enamel has formed on the tooth buds.
DEVELOPMENT OF JAW AND TEETH



Maxilla
(upper jaw)

Mandible
(lower jaw)





A NEWBORN BABY’S JAWS A FIVE-YEAR-OLD CHILD’S TEETH A NINE-YEAR-OLD CHILD’S TEETH AN ADULT’S TEETH
The primary teeth can be seen There is a full set of 20 erupted Most of the teeth are primary By the age of 20, the full set of
developing in the jaw bones; primary teeth; the permanent teeth but the permanent 32 permanent teeth (including
they begin to erupt around the teeth can be seen developing in incisors and first molars have the wisdom teeth) should be
age of six months. the upper and lower jaws. now emerged. in position.

THE PERMANENT TEETH

Molars Premolars Canines Incisors Canines Premolars Molars





UPPER




LOWER



3rd 2nd 1st 2nd 1st Lateral Central Lateral 1st 2nd 1st 2nd 3rd
(wisdom) (wisdom)

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TEETH
STRUCTURE OF A TOOTH
Cusp Enamel




Crown

Amelodentinal
junction Fissure

Dentine

Interdental papilla
Gingiva (gum)
Neck


Pulp horn


Pulp
Odontoblast chamber


Jaw bone


Volkmann’s
canal
Root Oblique fibre of
periodontium
Interdental
septum
Pulp vein
Root canal
Pulp artery
Interradicular septum
Pulp nerve

Cementum
Lateral canal
Apical fiber of
periodontium
Apical foramen




Alveolar bone
Alveolar artery
Alveolar vein


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THE HUMAN BODY

Digestive system



THE DIGESTIVE SYSTEM BREAKS DOWN FOOD into particles so tiny that blood can take nourishment
to all parts of the body. The system’s main part is a 30 ft (9 m) tube from mouth to rectum; muscles
in this alimentary canal force food along. Chewed food first travels through the esophagus to the
stomach, which churns and liquidizes food before it passes through the duodenum, jejunum, and
ileum—the three parts of the long, convoluted small intestine. Here, digestive juices from the
gallbladder and pancreas break down food particles; many filter out into the blood through tiny
fingerlike villi that line the small intestine’s inner wall. Undigested food in the colon forms feces
that leave the body through the anus.


Stomach


Cardiac notch











Esophagus

Left lobe of liver
Nasal Epiglottis Trachea
cavity
Uvula Falciform ligament
Oral
cavity Mandible
(lower jaw) Hepatic artery
Maxilla
(upper jaw) Tongue
Cystic duct
Tooth
Mouth
Right lobe of liver




Gallbladder
ENDOSCOPIC VIEWS INSIDE
ALIMENTARY CANAL

ESOPHAGUS STOMACH ENTRANCE STOMACH STOMACH EXIT


Ruga
Mucosa
Cardiac
orifice Pylorus




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