nAm I 8 I A unIVERSITY OF SCIEnCE AnD TECHnOLOGY

FACULTY OF HEALTH AND APPLIED SCIENCES

DEPARTMENT OF NATURAL AND APPLIED SCIENCES

QUALIFICATION: BACHELOR OF SCIENCE (MAJOR AND MINOR)

QUALIFICATION CODE: 07BOSC LEVEL: 5

COURSE: GENERAL BIOLOGY lA COURSE CODE: GNBSOlS

DATE: JULY 2016

DURATION: 3 Hours

EXAMINER(S)

MODERATOR:

SESSION:

MARKS: 110

SECOND OPPORTUNITY EXAMINATION QUESTION PAPER

Dr. Jeya Kennedy

Mrs. Louise Theron

INSTRUCTIONS

1. Write clearly and neatly

2. Number the answers clearly

3. All written work MUST be done in blue or black ink

4. No books, notes and other additional aids are allowed

5. Mark all answers clearly with their respective question numbers

THIS QUESTION PAPER CONSISTS OF 7 PAGES

(Including this front page)

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QUESTION 1: MULTIPLE CHOICES QUESTIONS [10]

1.1 The ultrastructure of a chloroplast is best studied using a; (1)

a) Light microscope

b) Telescope

c) Scanning electron microscope

d) Transmission electron microscope

1.2 Which of the following is mostly closely associated with protein synthesis? (1)

a) ribosomes

b) smoothER

c) mitochondria

d) microfilaments

1.3 A phospholipid molecule has a head and two tails. The tails are found; (1)

a) at the surfaces ofthe membrane

b) in the interior of the membrane

c) spanning the membrane

d) where the environment is hydrophilic

1.4 An mRNA molecule is produced by __ _ (1)

a) Replication

b) duplication

c) transcription

d) translation

1.5 According to the base-pairing rules, guanine binds with; (1)

a) cytosine

b) adenine

c) thymine

d) guanine

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1.6 Substances that can pass through cell membranes by diffusion include; (1)

a) Na+ ions

b) cr ions

c) glucose

d) oxygen

1.7 Pinocytosis involves the transport of; (1)

a) large particles out of a cell

b) fluids into a cell

c) whole cells into another cell

d) lysosomes out of a cell

1.8 When Mendel crossed a strain of tall pea plants with a strain of short pea plants, he

observed that all of the plants in the Fl generation were tall. This suggests that; (1)

a) the tall trait was controlled by a dominant factor

b) the short trait was controlled by a dominant factor

c) both traits were controlled by a recessive factor

d) the strain of short plants was not capable of pollinating the strain of tall plants

1.9 In a dihybrid cross between an individual with the genotype RRYYand an individual with the

genotype rryy, all of the offspring will have the genotype; (1)

a) RRY.

b) RrYY

c) RrYy

d) rryy

1.10 Replication of the two DNA strands takes place; (1)

a) in two different directions

b) in the same direction of the replication fork

c) in a direction opposite to that of the replication fork

d) at right angles to the direction of the replication fork

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QUESTION 2: FILL IN THE BLANK

2.1 Lipids called ______ are made of four, fused rings of carbon.

2.2 Prokaryotic organisms make up the kingdom ____ and ___ _

2.3 Methionine is called the_ (a)_ codon & is represented by the bases_ (b)_.

2.4 The chlorophyll molecules at the reaction center of photosystem II absorb wavelengths of

___ nm.

2.5

2.6

2.7

2.8

______ are organelles containing chlorophyll.

The ______ also known as the internal framework ofthe cell, consisting of

microtubules, actin filaments, and intermediate filaments.

The Calvin cycle does_ (a)_ require light energy and occurs in the

_(b) __ of the chloroplast.

Stacks of thylakoids are called _____ _

2.9 The short segments of the lagging strand are called ______ fragments.

2.10 The DNA strand that is copied is called the ______ strand.

QUESTION 3: ONE WORD ANSWERS

3.1 Who is the father of genetics?

3.2 How many hydrogen bonds link the base pair cytosine and guanine?

3.3 What part of the electromagnetic spectrum is utilised for photosynthesis?

3.4 What scientists showed the amount of the 4 nitrogen bases present in DNA?

[10]

(1)

(1)

(1)

(1)

(1)

(1)

(1)

(1)

(1)

(1)

[10]

(1)

(1)

(1)

(1)

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3.5 Which carbohydrate cannot be digested by humans and how does it help the

digestive system? (1)

3.6 Name the purines. (1)

3.7 What genotype results from this cross--- TI x tt? (1)

3.8 What would be the complementary RNA sequence for the DNA sequence- 5'- GCGTATG-3'? (1)

3.9 Fred Griffith worked with what type of bacteria? (1)

3.10 Where does the carbon that is used in photosynthesis come from? (1)

QUESTION 4: DEFINE THE FOLLOWING TERMS

4.1 Nucleus-

4.2 Endosymbiosis-

4.3 Alcoholic fermentation-

4.4 Phagocytosis-

4.5 Anticodon-

QUESTION 5: DISTINGUISH BETWEEN THE TERMS IN EACH OF THE FOLLOWING

PAIRS OF TERMS.

5.1 Cytoskeleton, microtubule-

5.2 Chlorophyll a, carotenoids-

5.3 Sex chromosome, autosome-

[5]

(1)

(1)

(1)

(1)

(1)

[10]

(2)

(2)

(2)

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5.4 Osmosis, turgor pressure-

5.5 Self-pollination, cross-pollination-

QUESTION 6: SHORT ANSWER

6.1 During DNA replication, what is the function of helicases and DNA ligase?

6.2 A homozygous dominant individual (AA) is crossed with an individual that is heterozygous

for the same trait (Aa). What are the possible genotypes of the offspring, and what

percentage is likely to show the dominant phenotype?

6.3

6.4

6.5

6.6

6.7

6.8

How do saturated fats differ from unsaturated fats, both in structure and in behaviour?

How do you make a wet mount?

Name 3 disaccharides and the simple sugars that make up each of the disaccharides.

List (six) the substances that a plant cell can make from G3P, the product of the Calvin cycle.

Make a sketch of a tRNA molecule with its attachment site and anticodon labelled.

What is the shape of tRNA?

How are secondary cell walls different from primary cell walls?

QUESTION 7: ANSWER THE QUESTIONS

7.1 Add up the energy captured (as ATP, NADH+, and FADH2) in each stage

of aerobic respiration.

7.2 Joan Berry (blood type A) gives birth to a daughter (blood type B) she claimed that the

father is David who's blood type is 0. Can he be the father (show all possible genotypes

in your answer) .

(2)

(2)

[22]

(2)

(2)

(2)

(3)

(3)

(3)

(3)

(4)

[18]

(5)

(5)

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7.3 Hershey and Chase confirmed that DNA, not protein, was the genetic material.

How do the results of their two experiments support this conclusion?

QUESTIONS 8:

ANSWER ONLY ONE QUESTIONS FROM THE SECTION BELOW

8.1 Distinguish between the four levels of organization of protein molecules.

OR

8.2 Give a brief overview of the four stages of aerobic respiration.

QUESTIONS 9: EASSY QUESTIONS

ANSWER ONLY ONE QUESTIONS FROM THE SECTION BELOW

9.1 Describe the flow of electrons through the noncyclic electron transport pathway

and the products produced.

OR

9.2 Name the three stages of translation. Briefly describe the key events of each stage.

THE END

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