a. Name five vertebrae in mammals with their corresponding locations. [10 marks]
b. State one function each of the following parts in a dicotyledonous leaf:
(i) palisade;
(ii) vascular bundle;
(iii) epidermis. [3 marks]
c. State one function each of the following parts in the stem of a flowering plant:
(i) sieve tube;
(ii) cortex;
(iii) pith.
d. In a tabular form, state:
(i) two external structural differences between the stem and root of a maize seeding. [2 marks]
(ii) two internal structural differences between the stem and root of a maize seeding. [2 marks]
Explanation
a. Vertebrae with corresponding location
|
Vertebrae |
Location |
|
Cervical |
Neck |
|
Thoracic |
Chest/Thorax |
|
Lumbar |
Abdomen/Upper abdomen/loin |
|
Sacral |
Hip/lower abdomen |
|
Caudal |
Tail/coccyx |
b. Function of:
(i) Palisade
- Manufactures food/carries out photosynthesis/site of photosynthesis;
- Contains chloroplasts for photosynthesis;
(ii) Vascular bundle
- Contains xylem for transport of water/mineral salts/phloem for translocation of manufactured organic substances/hormones;
- Provides mechanical support;
(iii) Epidermis
- It keeps the leaf’s shape;
- Provides mechanical support;
c. Function of
(i) Sieve tube
- Translocates/transports manufactured foods to other parts of the plant
(ii) Cortex
- The cells of cortex store starch;
- Outer cortex cells of green stems contain chloroplasts and make food by photosynthesis/chlorophyllus cortex cells manufacture food;
(iii) Epidermis
- Cells of pith act as packing/food storage tissues;
- Supports the stem;
d. Structural differences
(i) External structural differences between stem and root of a maize seedling
|
Stem of a maize seedling |
Root of a maize seedling |
|
Fibrous root absent |
fibrous root present |
|
Chlorophyllus/greenish |
non chlorophyllus/non-greenish |
|
Leaves are present |
leaves are absent |
|
Thicker in size |
thinner in size |
|
Coleoptiles/shoot sheath present |
coleoptiles/shoot sheath absent |
|
Coleorhizae/radicle sheath absent |
coleorhizae/radicle sheath present. |
(ii) Internal structural differences between stem and root of a maize seedling
|
Stem of a maize seedling |
Root of a maize seedling |
|
Vascular bundles are scattered |
vascular bundles are arranged/in a ring form |
|
More vascular bundles |
less vascular bundles |
|
Cortex is narrower |
cortex is wider |
|
Pith is absent |
pith is present |
|
Endodermis absent |
endodermis present |
|
Phloem and xylem do not alternate |
phloem alternates with xylem |
|
Piliferous layer absent |
piliferous layer present |