chapter 4 : chemical composition in a cell
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Chapter 4 : Chemical Composition in a Cell.Biology Form 4 Exercise.TRANSCRIPT
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
WORKSHEET 4.2 : The Chemical Compound in the cell
Fill in the blanks with the correct answer.
1.
2. Organic compounds contain the element ______________. For example _________,
_________, __________ and nucleic acids.
3. Inorganic compounds usually do not contain carbon atoms. For example ___________
[7 Marks]
The Importance Of Organic Compounds
Organic compounds Importance
Protein
Made up of the ___, ___, ___ and ___
elements, most protein also contain S
and P.
15% of protoplasm is made up of
protein.
Build new cells for ____________ and
renew damaged tissues.
Required in the synthesis of ___________,
antibodies and hormones.
Organic compounds Importance
Carbohydrates
Contain __, ___ and ___ .
The ratio of atom H to O is ______
Store in plant as _____________
Cellulose forms the _________ of plant cell.
____
Lipid
Protein
Water
Organic
Inorganic
Carbohydr
ates
The chemical compound in
the cell
Score __ /__ ____
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
A primary source of ____________
Store as ____________ in human and
animals cell.
Lipids
Contain ___, ____ and ___
Examples : fats, oil, waxes,
phospholipids and steroids
Act as a solvent for fat-soluble vitamin such
as A, ___, ___, ___
___________ a major constituent of the
plasma membrane
_____ prevent water loss in plants and
infection by pathogens.
Nucleic acids
___________ is a building block of
nucleic acids.
The structure of a nucleotide
Two types of nucleic acid:
a) deoxyribonucleic acid (DNA)
b) ribonucleic acid (RNA)
Store genetic material in the form of a code.
Nucleotide consists of a nitrogenous base,
pentose sugar and a phosphate group.
DNA
A _____________ polynucleotide
(double helix)
Found in _________, __________ and
____________
The genetic information is passed from the
parent to the offspring
RNA
A ______________ of polynucleotide
Found in _______________,
_____________ and _____________
Copies the information carried by DNA for
use in protein synthesis
[31 Marks]
Phosphate group
Pentose
group
Nitrogenous group
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
CHAPTER 4 : CHEMICAL COMPOSITION OF THE CELL
WORKSHEET 4.3 The importance of water in the cell
[10 Marks]
Score __ /__
____
SOLVENT
- Water is the universal _________
of many biological molecules
because of the polarity its
molecules
Moisture
- Water provides ___________ to
the respiratory surface (alveolus)
- This enables respiratory gases to
dissolve in them before
____________ across the
respiratory surface can occur.
MAINTAINING OSMOTIC BALANCE AND TUGIDITY
- Water maintains the __________
balance between blood and
interstitial fluid
- In plants, the cell sap in the
vacuole contain water. The cell
becomes turgid and this
_________ provides support to
plants.
LUBRICATION
- _________ assists the
movement of food substances in
the intestinal tract.
- Synovial fluid lubricates the joint
to ease the movements at the
joints.
MAINTAINING BODY TEMPERATURE
- Keep relatively constant body __________
for optimal enzymatic activities.
MEDIUM FOR BIOCHEMICAL REACTION
- Water acts as ____________for
biochemical reaction.
TRANSPORT MEDIUM
- transport sugar,
________________ and
respiratory gases.
- Remove waste products from
body such urea through urine and
sweat.
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
CARBOHYDRATES
WORKSHEET 4.4 : Types of Carbohydrates
Fill in the blanks with the correct answer.
Types Examples Characteristics
Monosaccharides
Glucose
(plants and fruits)
Fructose
(Sweet fruits and honey)
Galactose
(________________)
Taste ________
Water soluble
______________
Simplest carbohydrates
Able to crystallize
Disaccharides
Maltose
(Malt sugar)
Sucrose
(Cane sugar)
Lactose ( ___________)
Taste _______
Water soluble
Reducing sugar except _______
Able to crystallize
Polysaccharides
Starch (plant)
___________
(animal)
Cellulose (cell wall in plant)
Do not taste sweet
________ in water
Do not crystallize
[7 Marks]
Score __ /__ ____
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
CARBOHYDRATES WORKSHEET 4.5 : Formation and Breakdown of Disaccharides and Polysaccharides
Fill in the blanks with the correct answer.
MONOSACCHARIDES
DISACCHARIDE
POLYSACCHARIDE
A ___________ of
carbohydrates
Examples:
Glucose
Fructose
Galactose
Formed when two monomer
are joined together by
________________ reaction.
During this process, a
molecule of ___________ is
removed.
Can be broken down into
monosaccharide by
__________________.
The addition of water is
needed.
Examples:
Maltose (Glucose + glucose)
Sucrose (Glucose + fructose)
Lactose (Glucose + galactose)
A polymer formed by
____________ with
hundreds or thousand
glucose monomers
Examples:
Starch
Glycogen
Cellulose
Polysaccharides can
be ___________ into
smaller molecules
through hydrolysis by
adding dilute acids,
boiling and enzymatic
reaction.
[6 Marks]
CARBOHYDRATES
Consist of
Score __ /__
____
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
PROTEINS WORKSHEET 4.6 : The elements in protein
1. Protein are organic molecules which made up of the elements ____________,
___________, __________ and hydrogen. Some protein also contain sulphur and
phosphorus.
2. Protein are made up of monomer called __________________.
3. There are 20 types of amino acids in living cells. It can be divided into two groups the
_____________ amino acids and the _______________ amino acids.
[9 Marks]
_________ be synthesized
by the body.
Can be ________ from diet
Animal protein contain all
the essential amino acids.
They are called first class
proteins
Plant proteins do not
contain all essential amino
acids. They are called
second class protein.
Can be _____________ by
the body.
They are derived from other
amino acids.
There are 11 non-essential
amino acids.
Example: Glycine, Alanine
and Serine
A M I N O A C I D
Essential
Non-essential
Score __ /__
____
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
4. Complete the graphic organizer below. [4 Marks]
PROTEIN
Primary
Quaternary
Tertiary
Amino acid
Type
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
PROTEINS
WORKSHEET 4.7 : Structure of Proteins
1. One or more of polypeptides chains in a linear sequence or coiled can form
_____________ molecules.
2. There are 4 levels of structure in proteins, depending on the sequences of __________
and the coil of the _________________ chains.
Level of protein Structures
Information Figure
Primary structure
A _______ sequence of amino acids in a
polypeptide chains
Secondary
structure
Polypeptide chains that is coiled to form
________________ or folded
Into ___________________
Tertiary structure
It refers to the way the helix chain or beta-
pleated sheets are folded into three-
dimensional shape of a ______________.
Quaternary
structure
It refers to the combination of two or more
tertiary structure polypeptide chains to
form one large and _________________
protein molecule, e.g : haemoglobin
Score __ /__
____
[5 marks]
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
PROTEINS
WORKSHEET 4.8 : Formation and break down of dipeptides and polypeptides
1. When two amino acid molecules are joined together by a peptide bond through
condensation, a ______________ is formed.
2. A water molecules is removed during the _________________ reaction.
3. + + water
4. Further condensation reactions can link more amino acids to form a
_________________________ (more than 50 molecules of amino acids).
5. A dipeptide and polypeptide can be broken down into amino acids by means of
_______________________.
[6 Marks]
Amino acids Peptide bond
hydrolysis
Polypeptide +
Score __ /__
____
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
PROTEINS
LIPIDS
WORKSHEET 4.9 : The Element in Lipids
Fill in the blanks with correct answer.
1. Lipids are organic compounds consist of ____________, ___________________ and
_________________ like carbohydrates.
2. However, the ratio of hydrogen atoms to oxygen atoms in one molecule of lipid is much
higher than the 2 : 1 ratio in carbohydrates. (olive oil : C57H104O6).
3. Generally, lipids are insoluble in water but soluble in __________________
[4 marks]
The main types of lipids
Complete the graphic organizer below:
[5 marks]
L
I
P
I
D
S
Oil
Phospholipids
Found on the _______ of epidermis of leaves, fruits and seeds and seeds and also in sebum
Important component in the formation of
__________________
Complex organic compounds which include chlolestrol and hormones (testosterone, estrogen and
progesterone)
Score __ /__ ____
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
LIPIDS
WORKSHEET 4.10 : The Components of Fats and Oils
Fill in the blanks with correct answer.
1. Lipids which are solids at room temperature are called _____________________
2. Lipids which are liquid at room temperature are called ________________________
3. Each molecules of fat and oil consists of one molecule of _____________________ and
three molecules of _____________________
4. Fats and oils are called ____________________ because they are formed from three
molecules of _______________________________
[6 marks]
The formation and break down of fats and oils
+ + water
[2 marks]
Complete the table below :
Comparison between Saturated fats and Unsaturated fat
Saturated fats Characteristics Unsaturated fat
______________have any
double bonds between the
carbon atom.
Types of bond
____________ double
bond between carbon atom.
_____________________
Condition at room
temperature
___________________
Contain cholesterol
Cholesterol level
Usually __________
contain cholesterol
______________ fats like
butter
Examples
Vegetable oil like corn oil
and palm oil
[6 marks]
One
molecule of
glycerol
3 molecules
of fatty acids
One
molecule of
triglyceride
Score __ /__
____
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
ENZYMES
WORKSHEET 4.11 : The Role of Enzymes in Organisms
Fill in the blanks with the correct answers.
Why are enzymes needed in life processes?
3. Many biochemical processes occur in a cell simultaneously at all times in a series of
linked reactions.
4. Collectively, these biochemical reactions are called __________________.
5. Enzymes are ________________ which can speed up biochemical reaction in the cell
without themselves being changed at the end of the process.
6. Enzymes are synthesized by living organism to ______________ and speed up
biochemical reaction in the cells.
[5 marks]
Metabolism
Metabolic reaction that
_________ complex
molecules
Metabolic reaction that
______ down complex
molecules
Anabolism Anabolism
Score __ /__
____
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
ENZYMES
WORKSHEET 4.12 : General Characteristic of Enzymes
Complete the blanks with the suitable answers.
[9 marks]
C
H A
R A C
T E
R I S
T I
C
O
F
E N Z
Y M E
S
Specific
Biological catalyst
Sensitive to
T_________
Sensitive to ____
___________ concentration Affected
by
Needed in
small amounts
___________ concentration
The _________ temperature is the
temperature at which an enzyme
catalyses a reaction at the maximum
rate (37oC).
At high temperature, the enzyme will ________________________
The ____________ is the pH at which the rate of reaction is at maximum.
____________ the rate of
chemical reaction
Remain _____________ at
the end of the reaction.
Score __ /__
____
4.12/1
Name : _____________________________ Chapter 4 Chemical Composition of the cell __________________________________________________________________________________________
ENZYMES
WORKSHEET 4.13 : The mechanism of enzyme action (Lock and key hypothesis)
Fill in the blanks with the correct answer
enzyme-substrate complex
[6 marks]
Enzyme has an __________________
The active site has a fixed shape that
___________________ to its substrate.
That is why enzymes are highly
____________
The substrate molecule binds to the
active site to form an
_____________________________
Enzyme catalyses the substrate to form
______________________________.
The enzyme molecule now is free to
_______________ to more substrate.
The hypothesis for enzyme reaction
is called ‘lock and key’ hypothesis.
Active site
Score __ /__
____