Teknik Menjawab Soalan PSPM Biologi

PREPARATION FOR







BIOLOGY2 (SB025)












PSPM 2

Biology 2 A






Method and type of Assessment











Type of Method Percentage


Assessment (%)




Writing Test Final 60



Examination




Practical Test 10



Continuous Lab Report 15


Assessments
Assignment 15

Biology 2 A







Format for PSPM 2 Biology










Paper 1 Paper 2



Question 40 objectives question 9 Question- structured/essay





Topic All topic 1-10 All topic except for topic 1:
Biodiversity(this topic is in

assignment)




Total Marks 40 marks 100 marks





Duration 1 hour 2 hour 30 minutes

Paper 1 Paper 2 Biology 2 A

Taxonomy Taxonomy Level
Topic Marks Level Marks
Allocated Allocated
C1 C2 C3 C4




1 Biodiversity 9 / / Assignment / /


2 Ecology 5 / / 9 / /


3 Selection and Speciation 2 / / 7 / /



4 Biocatalysis 2 / / 7 / /



5 Cellular Respiration 5 / / 18 / /



6 Photosynthesis 2 / / 11 / / Taxonomy level:


7 Gaseous Exchange & its Control 2 / / 7 / /
C1 - Remembering

8 Transport System 5 / / 11 / /
C2 - Understanding
9 Homeostasis 2 / / 7 / /
C3 - Application
10 Coordination 4 / / 16 / /
C4 - Analysing
11 Immunity 2 / / 7 / /


Total Marks 40 100

Biology 2 A























Tips in answering Paper 2











Structured Questions

Biology 2 A







Tips in answering structured question














• READ the questions CAREFULLY





• Read the questions from the beginning. Not only




by looking at the diagram.





• There are important information given in the



question.

Biology 2 A







Tips in answering structured question








• The overall process of cellular respiration in liver cells is shown in FIGURE 4.

Biology 2 A



Tips in answering structured question








• Follow the instruction given in the question.










Example : Name the TWO molecules that are the by-products of the


conversion of pyruvate to acetyl coenzyme A. [2 marks]



Correct answer: CO and NADH
2



- Answer TWO molecules only. Do not give more than two.




- If the students give more than two molecules and the third answer is

wrong, no marks given to all the answers.

Biology 2 A






Tips in answering structured question








• Give 1 answer only for question ask to name certain things.





• Example: How many ATPs are produced from the substrate level phosphorylation

in the Krebs cycle from one molecule of glucose? [1 mark]




correct answer : 2ATP




DO NOT:





example: 2ATP / 1 ATPX

Biology 2 A





Tips in answering structured question







• Give 1 answer only for question ask to name certain things.





Example : What is the class for enzymes found in the ETC according to IUB?


[1 mark]



correct answer: Oxidoreductase









DO NOT:




example: oxidoreductase (oxidation-reduction enzyme)X






No bracket. State only one answer.

Biology 2 A







Tips in answering structured question













• For the certain terms that use name of a person, make sure to



write in capital letter.











Example: Krebs cycle, Calvin cycle, Hatch-Slack pathway, Islet of



Langerhans.

Biology 2 A





Tips in answering structured






question









• There are terms that must be underlined





• Eg: scientific name : E. coli

Biology 2 A





Tips in answering structured question








• For the questions that involve calculation, write the

formula first (if applicable), then show the calculation.



• Write the unit for the answer.



• Example: Based on the curves for pigment X and Y,


calculate the amount of oxygen released to the tissues at

20mmHg




Pigment x = 98% - 80%




= 18%


Pigment Y = 98% - 30 %



= 18%

Biology 2 A













Tips in answering







Paper 2












Essay Questions

Biology 2 A









Tips in answering Essay Question












• Write in paragraph form.











• For the question ask to about differences, students also have to


write in paragraph form, not in table form.

Biology 2 A









Tips in answering Essay Question












• For DIFFERENCES, write in paragraph.



• Example: Differentiate aerobic respiration and fermentation (8 marks)



Suggested Answer:




Aerobic respiration occurs in cytoplasm and mitochondria while fermentation occurs

in cytoplasm only



• use the word while / whereas as a link to give differences between two things.



• if the question is 8 marks, the answer has to be 8 differences.

Biology 2 A










Tips in answering Essay Question








• Do not write one sentence too long.




• If the first sentence is correct but the second sentence is incorrect, the whole sentence


is considered wrong.



• Example: Mostly enzymes are globular protein and specific (specific is incorrect)



- The whole sentence is considered wrong.



• Suggested answer :



Mostly enzymes are globular protein. Enzymes are highly specific

Biology 2 A









Tips in answering Essay Question









• Certain terms, example name of hormone, students have to write full


name in the first mention, then you can use the short form when mention

the second time.








• Example: Explain the osmoregulation in nephron. [5 marks]




If the concentration rises the osmoreceptor in hypothalamus will detect

and stimulate posterior pituitary gland to secrete Antidiuretic hormone


(ADH). ADH stimulate the distal convoluted tubule (DCT) and collecting

duct more permeable to water.

Biology 2 A

















List of words used in examination





questions.







Exam questions use various words that key you in


on how to approach the questions.

Biology 2 A






Compare

















- Write about the similarities and differences between two


topics




- You need to be organized




- Without careful planning you will produce a disorganized answer which


will be difficult to mark

•Define









- State the meaning of, for example, a term




without actually using the term itself

Describe






- a request for factual detail about a structure or process



expressed logically and concisely





- Example: Describe carbon fixation in C plants. [10 marks]
4

Suggested Answer:








1 M 1 M

C pathway is also called Hatch- Slack pathway. CO fix with phosphoenolpyruvate (PEP)
4
2
(in the mesophyll cells) to form oxaloacetate (OAA). This process catalyses by PEP
1 M
carboxylase.
1 M
1 M OAA will be converted to malate (4C). Malate is transported to bundle sheath cells. Malate

converted to pyruvate (3C)and releasing CO 1 M
1 M 2 1 M

CO react with RuBP to form PGA (3- Phosphoglycerate) in bundle sheath cell. Ribulose RuBP 1 M
2
carboxylase (rubisco) in Calvin cycle

1 M 1 M
Pyruvate is transported back to mesophyll cell and converted to PEP using energy from ATP C plants
4
have adaptation to fix CO efficiently 1 M
2

Discuss






- A critical account of the various viewpoints and


arguments in the topic set





- Drawing attention to their relative importance and



significance




- E.g: Discuss the advantages and disadvantages using



the pyramid number and pyramid of energy.

•Distinguish between















- State the differences between, for example, two or



more terms, often for the purpose of




identification.

•Explain















-describe and give reasons for,



-example:




Explain how helper T cell activates B cell.

•Graphs











- When a graph is being interpreted it is essential to relate



any changes or trends to its biological context, using data



as support where possible.

Review By Topics

TOPIC 1




BIODIVERSITY

BIODIVERSITY









Tips for answering objective questions




• Use 2B pencil not pen



• Read the questions carefully and understand what the question is asking (find


keywords)



• Read all the answers given first



• Choose the correct and the most accurate answers



• Please shade the OMR form correctly (makesure the circle is fully shaded)



• If you wish to change your answer, please erase the former answer clearly before


shading the new answer





TOPIC 2: ECOLOGY









● Graph – title of graph,
title of axis
Carefull between FOOD
●
CHAIN & FOOD WEB ● Difference between

exponential growtg curve
Ecologycal Pyramid not
● (Human) & Logistic
exceeds 5 trophic levels
growtg curve

Make sure the unit for energy
● (Paramecium sp.)
calculation is correctly written
● Density dependent factor
Illustrate the biogeochemical
● (example : desease,
cycle properly
source of food) & density
independent factor

(climate change, natural

disaster)

TOPIC3













SELECTION &








SPECIATION

TOPIC 3: SELECTION AND SPECIATION





List of possible questions:

a)With the aid of labeled diagram, analyze the types of natural selection

b) With the aid of labeled diagram, explain the types of natural selection

TOPIC 3: SELECTION AND SPECIATION

List of possible questions:








Compare stabilizing selection and

disruptive selection






























Compare stabilizing selection

and directional selection

TOPIC 3: SELECTION AND SPECIATION

List of possible questions:







Compare directional selection and

disruptive selection































a)Compare inbreeding and outbreeding
b) Compare and contrast inbreeding and

outbreeding

LIST OF POSSIBLE

QUESTIONS






a) Describe modes of

speciation.



b) What is speciation? Explain


two modes of speciation.



c) Define speciation. Describe


how sympatric and allopatric

speciation occur.

LIST OF POSSIBLE


QUESTIONS







a) Define reproductive isolation and describe two
types of reproductive isolating mechanisms.


b) Explain prezygotic and postzygotic mechanisms.


c) Explain the role of reproductive isolating

mechanism in preventing populations of different

species from interbreeding.


d) Explain reproductive isolation as a process that
lead to speciation.

LIST OF POSSIBLE

QUESTIONS







a) Describe genetic drift and two situations

that can cause genetic drift to occur


b) Describe genetic drift as a process that

lead to speciation

LIST OF POSSIBLE


QUESTIONS












Explain hybridization as a process that

lead to speciation





















Explain adaptive radiation as a

process that lead to speciation

TOPIC 4




BIOCATALYSIS

• globular protein. • decreasing the activation energy. Mechanism of enzyme action
Properties of enzyme
• increase the rate of reaction. • specific to its substrates Induced-fit model
Initial shape of active site does not exactly fit with the substrate
• do not change after the reaction. has active site which binds to its substrate.
•
• reusable after the reaction. • needed in small quantity. When substrate binds to the active sites, the shape of enzyme
active site slightly change
• denatured at extreme temperature or pH. Enable substrate to fit exactly in active site to form an
• maximum at optimum temperature or pH. Enzyme-Substrate complex
Substrate bind to active site by weak bonds (ionic bond/Hydn bond)
Shape of substrate is slightly changed
Existing bonds are broken
Enzyme classification Transition state is achieved, reaction occurs
BIOCATALYSIS Products are formed


Oxidoreductase- catalyzed oxidation-reduction reactions Shape of products differ from substrates
Transferase -catalyzed transfer of a chemical group Products no longer fit into active site
Hydrolase - Breaking a molecule by hydrolysis reactions Products are released from active site
Isomerase- rearrangement of atom within a molecule Inhibitor Active site change back to the original conformation
Lyase- Breaking a molecule without using water
Ligase- Formation of bonds between two molecules using energy
derived from the breakdown of ATP Factors that affect enzymatic reaction

reversible irreversible
Substrate concentration
pH
Temperature

Cofactor
Competitive Non-competitive

Definition
Example competitive inhibitor:
Enzyme : Succinate dehydrogenase Enzyme is a biological catalyst which increase the rate of
Substrate : Succinate biochemical reaction in living things The minimum energy needed to
Product : Fumarate break the existing bond before a
Competitive inhibitor : Malonate by lowering the activation energy (E ) reaction can occur
a
and it remains unchanged at the end of reaction

4.1 (e) Explain the factors that affect the enzymatic reaction






















pH
Temperature Most enzyme function at a maximum

Substrate concentration At low temperature, rate of reaction is very slow rate over a narrow pH range

At low substrate concentration, the The kinetic energy of the molecules is low Changes in pH above or below the
rate of reaction increase as substrate Molecules move slowly optimal pH value will change the
concentration increase.
Therefore, the chances of substrates to collide with active site is low hydrogen ion concentration
There are many active sites of enzyme
than substrate. When the temperature increase, the kinetic energy of the substrate This ion changes the ionic charge of
and enzyme increase
Not all active site are occupied. the acidic and basic groups of amino
More enzyme-substrate complex is formed acids of the enzyme.
As [substrate] increase, more active
site are occupied until of of them bind The rate of reaction increase The ionic bonds that hold the
to its substrate.
For every 10°C rise in temperature, the rate of reaction is doubled specific 3D shape of enzyme are
The rate of reaction reaches the disrupted.
maximum rate. As temperature exceeds optimum value, the weak bond such as ionic
bond, hydrogen bond, hydrophobic interaction that holds the three
Increasing [substrate], does not affect dimensional shape of enzyme are broken down Active site are destroyed, enzyme
the rate of reaction since all active denatured
sites are saturated with substrate. Change the conformation of active site and enzyme become
denatured Rate of reaction decreases quickly.

Substrates cannot bind into the active site of the enzyme

Rate of reaction reduce drastically

14.2 Cofactor : A non protein components needed for some enzyme to increase enzymatic reaction




COFACTOR







Inorganic Organic





Non-protein molecules Non-protein molecules
bind loosely to the enzyme bind tightly to the enzyme




A: Metal ions B: prosthetic group C: coenzyme



Role: involve in catalytic Role: detach and help to transfer
Role: change the enzyme active site function of chemical group
to make the shape more suitable for the enzyme

reaction to take place
eg: NAD , NADP , coenzyme A,
+
+
eg. FAD, FMN, biotin, ATP
2+
eg. Ca (in thrombokinase), Mg 2+ haem
Ferum, Cobalt, Copper, Zinc

14.3 Inhibitor: A substance that reduce the rate of enzyme reaction




















Competitive Inhibitor Non competitive Inhibitor




A : active site A : active site
D : competitive inhibitor B : allosteric site
E : substrate C : non competitive inhibitor





-Competitive inhibitors have similar -Non competitive inhibitors have different
structure with substrate
structure with substrate -It binds to the allosteric site of enzyme
-It competes with substrate to bind -This will cause shape of active site is altered

to the active site of enzyme -Substrate cannot bind to the active site as

-The effect of competitive inhibitor long as non competitive inhibitors bind to
allosteric site
can be overcome -The activity of enzyme is restored to normal

-By increasing the concentration of when the inhibitor is removed

substrate -The effect of non competitive inhibitor
cannot be overcome

TOPIC 5













CELLULAR








RESPIRATION &








FERMENTATION

• Explain processes using correct terminology.




Example:




Glucose undergoes phosphorylation to form glucose-6-


phosphate OR glucose is phosphorylated to form glucose-6-


phosphate




NOT, glucose is converted to form glucose-6-phosphate










Malate is oxidised to form oxaloacetate



NOT, malate convert into oxaloacetate.

• Substrate/substance must be written in correct way.



Example:

Coma

between

number


Fructose-1,6-bisphosphate




















1,3-bisphosphoglycerate

Terminology Reaction



Remove 2 hydrogen atom (H)
Oxidation

Remove 2 electron (e )
-



Reduction Receive 2 hydrogen atom (H)


-
Receive 2 electron (e )



Phosphorylation Add inorganic phosphate (Pi)





Decarboxylation Remove CO 2




Isomerisation Rearrangement structure of molecule