Bio Assignment

BIOLOGY SB015
2022/2023

BIOLOGY FLIPBOOK

Molecules Of Life & Cell
structures and functions

Name : SITI SARAH BINTI RIDZUAN

Matric Number : MS2113173499

Practicum : K4T01A

Lecturer Name : ANIZA BINTI ABU BAKAR

QUSEESTTIAONS

5. DNA and RNA Molecules

1. Water

THE MAIN 4. Proteins
TYPES OF
MOLECULES
2. Carbohydrates OF LIFE

3. Lipids

Structure Of 2. Two hydrogen atoms 3. Water is a polar molecule
Water form polar covalent bonds • a polar molecule: have o
Molecule 1. Consists of an oxygen (sharing of electrons with
atom & two hydrogen an oxygen atoms) pposite charges (unequal
distribution of e lectrical
atoms. charge)
• oxygen region has a partial
negative charge (∂-)
• both the hydrogen regions
have a p artial positive
charge (∂+)

5. Water molecules are held together 6. Each water molecule c an

by a h ydrogen bond.

4. Angle between the 2 • formed when hydrogen atom is form hydrogen bonds with up to
attracted to another strongly maximum 4 other water
hydrogen atoms is 104.5° electronegative atom molecules.
• 3 atoms form a wide V • a partial positive (∂+) • hydrogen bonds are weaker
hydrogen of one H2O molecule
shape, not a straight line. is attracted to the partial than covalent bonds

negative ( ∂-) oxygen of nearby • but they are strong enough to
H2O molecule.
hold H2O molecules together

iii SWater has a high latent heat of vaporization. High amount of heat energy (580 calories of heat) is
required or absorbed to turn 1g of water from liquid state into water vapor. As we all know, main
purpose of sweating is to cool down our body temperatures. It takes energy to evaporate sweat off
our skin, and that energy is heat. So when a person’s body temperature begins to rise, they sweat.
Evaporation of sweat uses a lot of energy. This energy has a cooling effect to the skin. The cooling
effect helps to prevent overheating.
As for animals that do not sweat, they will bathe or wet themselves with water. This helps them to
prevent their bodies from overheating during hot days. For an example, an elephant will sprays
water from its trunk onto his head. Evaporation of this water cools the elephant down.

THE STRUCTURE OF WATER MOLECULE

ELECTRON MODEL BALL-AND-STICK SPACE-FILLING
MODEL MODEL

Water molecules move into or out of cell through osmosis.
Osmosis is a passive transport process that is similar to
diffusion but it involves only water molecules from an

area of higher water potential (low solutes concentration)
to an area of lower water potential (lower water
potential region) randomly through a selectively
permeable membrane. The selectively permeable

membrane is permeable to water but impermeable to
some solutes. The same situation occurs in cells through

phospholipid bilayer.

Simple Diffusion VS Facilitated
Diffusion VS Osmosis

DIFFERENCES SIMPLE DIFFUSION FACILITATED DIFFUSION OSMOSIS
TYPE OF MOLECULE
Small noncharged molecules or Involves insoluble compounds Water molecules
PRESENCE OF MEMBRANE lipid soluble molecules such as sugars, amino acids and
ions

Does not require the assistance Presence or absence of a A membrane is essential

of membrane membrane

REQUIREMENT OF No carrier phospholipids Carrier/channel protein Aquaporins (protein)
TRANSPORT PROTEIN

SIMILARITIES 1. Passive transport, do not require ATP
2. Move down concentration gradient

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