2023 NABTEB GCE Biology Alt to Practical Answers – Nov/Dec

NABTEB GCE 2023 BIOLOGY PRACTICAL ANSWERS
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(1a)
16 offsprings

(1b)
(i) Gonorrhoea: Neisseria gonorrhoeae.

(ii) Malaria: Plasmodium

(1c)
Insulin helps regulate blood sugar levels in animals by allowing cells to take in glucose for energy.

(1d)
The trait for flower color exhibits incomplete dominance.

(1e)
(i) It is a crucial component of amino acids, proteins, and chlorophyll, supporting plant growth and development.
(ii) Nitrogen is also involved in the synthesis of DNA and RNA, essential for genetic information and cell division.

(1f)
(i) Wind speed: Anemometer
(ii) Turbidity: Turbidimeter

(1g)
Anemia

(1h)
The dental formula in man is 2-1-2-3 / 2-1-2-3, which means there are 2 incisors, 1 canine, 2 premolars, and 3 molars in each half of the upper and lower jaws, making a total of 32 permanent teeth.

(1i)
(a) Xylem transports water and minerals from the roots to the rest of the plant.
(b) Phloem transports sugars and nutrients from the leaves to other parts of the plant.

(1j)
(i) Amoeba Proteus: Pseudopodia
(ii) Paramecium caudatum: Cilia

(1k)
(i) Increased Competition for Resources
(ii) Higher risk of spreading diseases

(1l)
(i) Microbial growth
(ii) Enzymatic activity
(iii) Oxidation
(iv) Physical damage.

(1m)
(i) The presence of air-filled spaces in their tissues to aid buoyancy
(ii) The ability to efficiently absorb nutrients from the water.

(1n)
Aorta

(1o)
(i) Carbohydrate: Monosaccharides
(ii) Protein: Amino acids
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(2ai)
Frog

(2aii)
a – Eye
b – Mouth
c – Digit
d – Hind limb

(2bi)
Amphibia

(2bii)
Ponds, lakes, or wetlands

(2c)
(i) Moist skin that allows them to breathe through their skin.
(ii) Webbed feet for efficient swimming and jumping.
(iii) Powerful hind legs for leaping and catching prey.
(iv) Bulging eyes on the top of their head for a wide field of vision.

(2d)
(i) Salamander
(ii) Newt
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(3ai)
Fig.2 : Thoracic vertebrae of mammal
Fig.3 : Scapula/shoulder blade of mammal

(3aii)
It is located in the upper thoracic region on the dorsal surface of the rib cage.

(3b)
I – Spine
II – Transverse costal facet
III – Superior articular process
IV – Inferior articular process
V – Inferior costal demi facet
VI – Rib facet
VII – Superior costal demi facet
VIII – Body
IX – Medial border
X – Spine
XI – Infraspinous fossa
XII – Glenoid cavity

(3ci)
Lateral view

(3cii)
– III(Superior Articular Process): It articulates (forms a joint) with the corresponding inferior articular process of the vertebra directly above it, creating a facet joint.

– V(Inferior costal demi facet): It articulates with the head of a rib.
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(4a)
AIM: To compare the water retaining capacity of sandy, loamy, and clayey soils.

APPARATUS: Filter funnel, cotton wool, measuring cylinder, sandy soil, loamy soil, and clayey soil samples, water.

METHOD: Fill the filter funnels with equal amounts of each soil type, add water, and measure the volume of water retained by each soil type over time.

(4b)
Draw the diagram

(4bi)
OBSERVATION:
(i) Sandy soil will allow water to pass through quickly and retain the least amount.
(ii) Loamy soil will have moderate water retention.
(iii) Clayey soil will retain the most water with slower passage.

(4bii)
CONCLUSION:
(i) Sandy soil has the lowest water retaining capacity.
(ii) Loamy soil has a moderate water retaining capacity.
(iii) Clayey soil has the highest water retaining capacity.
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(5a)
(i) Genetic traits
(ii) Behavioural traits
(iii) Physiological traits
(iv) Inherited diseases

(5b)
(i) Blue flower color is dominant.
(ii) White flower color is recessive.

(5c)

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Completed!!!
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