Animals tissue

Blood

• It is a connective tissue
with fluid matrix

• Consists of blood cells
and plasma

Plasma

• Plasma is the ground substance of blood
• Plasma is a pale yellowish coloured liquid.
• Plasma consists of water, proteins, salts and a variety of

soluble chemical messengers such as hormone
• That it transport from one part of the body to another

Blood cells

• Main component of
blood cells are

a. Erythrocytes
b. Leucocytes
c. Platelets

Erythrocytes

o The most numerous blood
cells (5 to 6 million per cubic
mm)

o Biconcave shape ( thinner in
the center than at its edges).

o Size about 7-8 µm in a
diameter

o Lack nuclei and organelles

o Erythrocytes production
occurs in the bone marrow

o Function : carry O2 and CO2

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Extra: Adaptation of erythrocyte

1. Has biconcave disc shape to increase surface
area for effective gaseous exchange
2. Has no nucleus when the cells reach
maturity to provide more space for
haemoglobin storage
3. Has flexibility to change the shape
easily the movement in blood capillary

Leukocytes

5 major
types:

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Leukocytes

DIVIDED INTO TWO GROUPS

AGRANULOCYTES GRANULOCYTES

 Non-granular  Granular cytoplasm
cytoplasm
 Nucleus with polymorph
 Have bean shape shape, S-shaped or doubled-
nucleus lobed

 Mature in lymph  Amoeboid
nodes
 Mature in bone marrow
 Lymphocytes and
monocytes  Neutrophils, Eosinophils,
Basophils

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Leukocytes

Their function is to defend the body
againsts diseases causing by
microorganisms

Monocytes
- Have large bean-shaped nucleus
- are phagocytes which engulf and
digest bacteria and dead cells.

Lymphocytes
- Become specialized as B
cells and T cells which produce the
immune response against foreign
substances

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• Neutrophil
- Most abundant of the leucocytes.
- Responsible for phagocytosis of
microorganisms

• Basophil
- Have S-shaped nucleus and
granules
- Secrete large amounts of histamine
(which increases inflammation)
- Secrete heparin (which helps to
keep a balance between blood
clotting and not clotting)

• Eosinophil
- Have a doubled-lobed nucleus
- Help control the allergic response

Size of cells about 2 – 3
µm in diameter
No nuclei
Originate as pinched – off
cytoplasmic fragments of
large cells in the bone
marrow
Function : important in
process of blood clotting

Differences between RBC and WBC

Red blood cells White blood cells
• Absence of Nucleus
• Function in transporting • Presence of nucleus
oxygen and carbon dioxide • Function in defend the body
• Flexible or fix
shape againsts diseases causing by
microorganisms
• Shape is irregular or
ammeboid