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.
Explanation
Specimen B - whole liver from a domestic fowl
Specimen D - gizzard
Specimen E - Intestine
(a) Phylum: Chordata / Vertebrata
Class: Aves
(b) Observable features of specimen B
- reddish/dark red colour
- has a greenish sac attached to it (presence of gall bladder)
- cone shaped
- soft and spongy to touch
c(i) Functions of specimen B to the organism from which it was obtained
- regulation of blood sugar level
- deamination of proteins/excretion of nitrogenous waste
- formation of fibrinogen
- produce heat for maintaining constant body temperature
- stores Vitamin A, B, D and E.
(ii) one function each of specimens D and E to the organism from which they were obtained.
Specimen D - help domestic fowl break down food into smaller, more digestible pieces.
Specimen E - digest food and absorb nutrients from it.
(iii) one adaptation each of specimens D and E to the function stated in 1c(ii)
D: a thick muscular wall, a hardened cuticle, and sometimes small stones called gastroliths.
E: have a short, efficient digestive system that's adapted for fast digestion.
(d)(i)
| Test | Observation | Inferences |
| Red litmus paper + fluid | fluid turns litmus paper blue | Basic or alkaline |
| Blue litmus paper + fluid | Blue litmus paper remains unchanged | Not acidic but basic or alkaline |
(ii) Functions of Bile
- breaks down fat globules into smaller pieces so they can be digested
- helps the body absorb fat, cholesterol, and fat-soluble vitamins
- neutralizes the acidic chyme from the stomach
- carries bilirubin, a waste product from red blood cells, out of the body in faeces
- carries excess cholesterol out of the body
- has antibacterial properties that help fight microorganisms in food.
e(i) The biological system in the body of vertebrates that specimens D and E belongs to is the Digestive system.
(ii) Specimen D (gizzard) is absent in human
f(i) The mode of feeding of the organism that possesses specimen E(intestine) is heterotrophic/ holozoic mode of nutrition.
(ii) The type of food that the organism that possesses specimen D consumes.
- grains
- seeds
- crops
- insects