SSCE/WASSCE/GCE PASS QUESTIONS AND ANSWERS
OBJECTIVES / MULTIPLE CHOICES
1. Proteins may be used in the
Use the list of parts of the alimentary canal below to answer question 3 to 4
Transparent eyelid |
Nostril at the tip of the nose |
I |
Homodont teeth |
Scaly skin |
III |
II |
Eye at top of head |
IV |
V |
22. Which of the labelled parts enable the animal to stay under water most the time?
A. I, IV and V C. I, III and IV
B. I, II and V D. III, IV and V
23. Two characteristics features of the class to which the crocodile belong are
- I and II C. II and IV
- III and IV D. II and V
IV |
III |
II |
I |
25. The part that is similar to the bone is labelled
A. IV B. III C. II D. I
26. The part labelled I and II constitute the
A. Crown
B. neck
C. root
D. gum
A. protein C. fat
B. starch D. mineral salt
28. In million's test, when the reagent is added to a protein food item,
a white precipitate is produced which turns
A. blue on heating C. green on heating
B. yellow on heating D. red on heating
29. After a meal of yam has been digested, the highest concentration of
glucose is to be found in the
A. hepatic artery
B. pulmonary vein
C. hepatic portal vein
D. posterior vena cava
30. Which of the following functions is performed by the liver?
A. deamination of amino acids
B. Secretion of sebum
C. Storage of bile
D. Storage of glucose
Answers
1. C |
7. C |
13. D |
19. A |
25. D |
2. D |
8. C |
14. C |
20. D |
26. A |
3. B |
9. C |
15. A |
21. A |
27. C |
4. A |
10. A |
16. D |
22. B |
28. D |
5. C |
11. C |
17. D |
23. B |
29. C |
6. C |
12. A |
18. C |
24. B |
30. A |
Theory
1. (SSCE 1994 Q4) (a)(i) What are enzymes?
(i) List the factors that can affect enzymes action
(ii) What is the source and role of each of the following enzymes?
(α) Salivary amylase
(β) Pepsin
(γ) Trypsin
(b) What is the role of the pancreas in carbohydrates digestion in mammals?
Solution
(i) Refer to notes
(ii) Factors affecting enzymes action
Enzyme concentration;
temperature; nature of the substrate; pH; Coenzymes, Concentration
of substrate
(iii)
Name of
enzyme |
Source |
Role |
Pepsin |
Gastric glands |
Break down of proteases and peptones |
Trypsin |
Pancreas |
Breaks down proteins, and peptones
into polypeptides |
Salivary amylase |
Salivary glands |
converts cooked starch into maltose |
(b) Pancreas produces pancreatic juice containing pancreatic amylase, which breaks down starch into maltose.
2. (SSCE 1995 Q1) (a) What is a protein
(b) Why are proteins required by animals?
Solution
(a) Proteins are complex organic compouds containing carbon, hydrogen, oxygen and nitrogen. Some proteins may also contain sulphur and phosphorus.
(b) Importance of proteins
Refer to notes
3. (SSCE 1996 Q2) (a) What are enzymes
(b) Describe five general characteristics of enzymes.
(c) Discuss what happens to a meal of rice and beans as it passes through the mouth to the small intestine of man.
Solution
(a) & (b) - Refer to notes
(c) Beans are proteins and rice is a carbohydrate. In the mouth the rice and beans are both chewed. The rice is being acted on by salivary amylase and change to maltose. In the stomach, pepsin in the gastric juice converts the beans into peptides. In the duodenum, pancreatic amylase converts the remaining rice to maltose. In the small intestine maltase converts maltose into glucose. Trypsin converts the beans to polypeptides. In the small intestine maltase converts maltose into glucose. Erepsin converts peptides into amino-acids. The glucose and the amino acids are absorbed into the blood stream.
4. (SSCE, 2000 Q7) (a) Give an account of the adaptation of mammals to a carnivorous mode of life.
Solution
1. Good night vision for hunting at night
2. Have claws for holding preys
3. Well-developed incisors for cutting or nipping pieces of meat
4. Dagger-like canines for piecing prey and tearing meat
5. Cusped premolar and molars for cracking bones
6. Upper jaw wider than lower jaw to facilitates shearing action
7. Powerful jaw muscles and up and down jaw action to avoid dislocation
8. Fasting moving with a well developing sense of smell which help in prey detection and its apprehension.
5. (SSCE, 2002 Q1) (a) Give a summary of the functions of the different parts of the human digestive system (names of enzymes and end products of digestion not required
(b) What are the adaptations observed in the alimentary canal of a carnivore and that of a herbivore?
Solution
Mouth (oral cavity): is a specialized organ for receiving food, breaking up large organic compounds secreting enzyme and digestion of starch.
Pharynx: swallowed food into esophagus
Oesophagus: forms bolus
Stomach: stores and break down food. It is on the left upper part of the abdominal cavity. It secretes protein digesting enzymes and strong acids to aid in food digestion.
Small Intestine: complete digestion and absorbs end products
Large Intestine: absorbs water, sodium and other ions but it excretes other metallic ions into the wastes.
(b) Adaptation of herbivore and carnivore in mode of nutrition
Refer to notes for detail
6. (WASSCE 2007 Q2) (a) Name four organelles in the living cell that produce enzymes and the enzymes produced in each case.
(b) State; (i) two local sources of proteins
(ii) two importance of proteins to human
(c) Briefly describe the digestion of a fish from the mouth to the point where it is absorbed into the body.
Solution
(a)
Organelle |
Enzyme |
Lysosome |
Lysozyme |
Nucleus |
DNA polymerase |
Mitochondrion |
Oxidase reductase |
Chloroplast |
ATP synthetase or carboxylase |
(i) Local source of protein: Soya beans, groundnuts, milk,
meat, fish, crayfish etc.
(ii) Refer to notes
Digestion of boiled fish: fish is proteins. In the mouth the fish is chewed into smaller particles, rolled into a bollus. The food is swallowed into the stomach through the oesophagus. Digestion of protein begins from the stomach. In the stomach, is produced which contains HCl and pepsin. HCl provide correct medium for effective action of pepsin. Pepsin converts fish into peptides. The stomach churns the food in watering chime which passes into the duodenum. The pancreas secretes pancreatic juice containing trypsin which converts the proteins into polypeptides. In the ileum intestine erepsin converts peptides into amino-acids. Amino acid is absorbed by diffusion through the villi in the ileum into the blood stream.
7. (WASSCE 2008 Q2) (a) What is balanced diet?
(b) (i) Name four classes of food.
(ii) Name one source each of the classes of food named in (i)
(c)(i) State three function of protein in human
(ii) Describe the appearance of a child whose diet is deficient in protein
(d) (i) Name one organelle in a living cell, that produce enzymes
(ii) Mention two enzymes that act on protein.
Solution
(a) Balanced diet: A diet that provides all the six classes
of food in the correct proportion.
(b) Classes of food: Carbohydrate,
Proteins, Fats/oils, Vitamins, minerals salts and Water
c) (i) Refer to notes
(ii) Appearance protein deficient child
1. Loss of weight
2. Thin limbs
3. Stunted growth
4. Kwashiorkor
5. Skin cracks
6. Swollen leg
7. Change in hair colour
(d) (i) lysosome, nucleus, mitochondrion,
chloroplast
(ii) Pepsin, renin, erepsin, trypsin
8. (WASSCE 2009) Describe the biuret test for protein in a given food substance
(c)(i). Name the disease that results from deficiency in vitamin C
(ii). List three symptoms of the disease named in (c) (i) above
Solution
Biuret test: An aqueous sample of a given food in a test tube, is treated with an
equal volume of 1% strong base (sodium or potassium hydroxide) followed by a
few drops of aqueous copper (II) sulphate. If the solution turns purple,
protein is present.
(c)(i) Disease: Scurvy
(ii) Symptoms
1. Weakness of the body
2. Loosening of teeth
3. Poor healing of wounds
4. Bleeding of gums/sore mouth
5. Anaemia
6. Reduced resistance to disease
7. Swellings of joints/gums
9. (WASSCE 2012) (a) Name one dental disease.
(ii) State the causes of dental diseases
(b)(i) Describe digestion of a meal meat and yam as it passes through the alimentary canal of human.
(ii) State two uses of each of the digested products of the meal mentioned in (i) above.
Solution
(a)(i) Dental disease
Periodontal disease or Tooth decay
(ii) Refer to notes
(b) Digestion of a meal of meat and yam
In the mouth: Meat is protein and yam is a carbohydrate. In the mouth the meat
and yam are both chewed into smaller particles. The yam is being acted on by
salivary amylase and change to maltose.
In the stomach: the stomach wall secretes gastric juice which contains pepsin,
renin and hydrochloric acid. The pepsin in the gastric juice converts the meat
into polypeptides.
In the duodenum: Pancreas produce pancreatic juice which contain amylase, trypsin and lipase. Amylase converts the remaining starch in the yam into maltose. Trypsin converts the proteins in the meat into polypeptides. In the ileum, intestinal juice called sucus entericus is secreted containing maltose, lactose, sucrose, erepsin. Maltase converts maltose into glucose. Erepsin converts peptides into amino-acids. The glucose and the amino acids are absorbed into the blood stream.
(ii) Uses of digested products
Glucose:
1. Utilized in body cells to release energy
2. Converted to glycogen in the liver muscle for storage
For synthesis of complex compound
Amino Acid:
1. Synthesis of protein
Enzymes and hormones formation
2. Growth and repair of damage tissues
10. (WASSCE 2014) (a) Define the following terms
(i) Elimination
(ii) Secretion
(b) Describe the digestion of boiled fish in the gut humans
(c) Make a diagram, 8-10cm long of a longitudinal section of a villus and label fully.
Solution
(a) (i) Elimination: is the removal of unwanted substance from
the body of living organisms.
(ii) Excretion: is the removal of metabolic waste products
from the cells of an organism, that may be poisonous if accumulate in the body.
(iii) Secretion: is the release of substance useful to the body by specialized glands of living organisms.
(b) Digestion of boiled fish in the gut humans
Boiled fish is proteins. In the mouth the fish is chewed and swallowed into the stomach. Digestion of protein begins from the stomach. In the stomach, pepsin in the gastric juice converts fish into peptides. In the duodenum, trypsin converts the fish to polypeptides. In the small intestine erepsin converts peptides into amino-acids.
mucus secreting cell (goblet cell)
Diagram of the longitudinal section villus
lacteal
venule
blood capillaries
outer layer of cell (epithelium)
lymphatic vessel
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