(a)A piece of raw meat was left in an uncovered bowl for seven days. Use the information to answer questions 3(a) and 3(b).
(i) State four likely changes that would be observed in the meat.
(ii) Name the biological process that led to the changes that are observed in the meat.
(iii)On the table below, list four methods of preserving meat to prevent it from the changes stated in 3a(i) and mention the principle involved in the methods.
| Four methods of preserving the meat | One principle involved in the preservation method |
(iv)Name two environmental factors that may be responsible for the changes in 3a(i)
(b) Name one method of preserving the following food items:
(i) dried maize grains; (ii) fresh tomatoes; (iii) vegetables; (iv) beans; (v) milk
a(i)Complete the table below by stating the type of cell division and the type of set of chromosomes for the listed cells.
| Cell | Type of cell division | set of chromosomes |
| Onion cell | mitosis | |
| Sperm cell | ||
| Pollen grain | ||
| Ovum | ||
| Guard cell | ||
| Cheek cell | diploid |
(ii) What is mitosis?
(b)Explain briefly how parents with blood groups A or B could have an offspring with blood group O.
(c)Explain briefly how genes are involved in the process of evolution.
SECTION B
a(i)What is competition?
(ii)List two types of competition.
(iii)List four factors that organisms compete for in a habitat.
(iv)Explain briefly the relationship between competition and succession.
b(i)What is structural adaptation?
(ii)State four types of structural adaptations in animals.
(c)List four features of variation in humans that are used in crime detection.
(d)Complete the table below by listing three types of adaptive colouration in animals and give one example each of animals that show the colourations.
| Three types of adaptive colouration in animals | One example of animal that show the type of colouration |
(e) Give three examples of plants found in a tropical Rainforest.
SECTION A
Study specimens B, D and E and answer questions 1(a) to 1(f).
(a) Name the phylum and class of the organism that possesses specimen D.
Phylum:
Class:
(b) State three observable features of Specimen B.
c(i) Give three functions of specimen B to the organism from which it was obtained
(ii) State one function each of specimens D and E to the organism from which they were obtained.
D:
E:
(iii) Mention one adaptation each of specimens D and E to the function stated in 1c(ii)
D:
E:
d(i) Use the office pin provided to prick the dark green structure attached to specimen B. Touch the fluid oozing from the structure with each of the red and blue litmus
papers at intervals. Record the observations and inferences on the table below:
| Test | Observation | Inferences |
| Red litmus paper + fluid | ||
| Blue litmus paper + fluid |
(ii) Give three functions of the fluid tested in 1d(i) to the organism that possesses it.
e(i) Name the biological system in the body of vertebrates that specimens D and E belongs to.
(ii) Which of specimens B, D or E is absent in humans?
f(i) Name the mode of feeding of the organism that possesses specimen E.
(ii) Name one type of food that the organism that possesses specimen D consumes.
Study specimens F, H and K and answer questions 2(a) to 2(d).
(a) State four functions of specimen H to the plant from which it was obtained.
b(i) State one function each of specimen F and K to the plants from which they were obtained.
F:
K:
(ii) Give one reason for the answers in 2b(i)
F:
K:
(iii) What part of the plant is modified for the function stated in 2b(i)?
F:
K:
c(i) State four observable differences between specimens F and K.
| F | K |
(ii) State one similarity between specimens F and K.
(d) Make a drawing; 6 cm to 8 cm long of the specimen H and label fully.
