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THEORY
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Section B Answer 3 Only
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1ai)
Classification of living things is the way in which all living things are placed into larger and larger groups or catetories that share similarities and a common ancestry.
1aii)
Carl Linnaeus
1aiii)
i)It allows scientists to identify, group, and properly name organisms via a standardized system
ii)to make it easier to study and understand their behaviors,
iii)To study evolutionary progression of millions of life forms
1aiv)
i)Kingdoms
ii)Phylum
iii)Classes
iv)Order
v)Families
vi)Genus
vii)Species
1bi)
i)they can reproduce
ii)they can mutate
1bii)
i)they do not carry out metabolism on their own hence they do not grow
ii)they contain no cytoplasm or cellular organelles
1ci)
i)mosaic disease of cassava
ii)swollen shoot disease of cocoa
1cii)
i)human immunodeficiency virus (HIV)
ii)measles
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6a)
The odorous molecules come into contact with the olfactory epithelium at the top of the nasal cavity and stimulate multiple chemically cell receptors and thus the odour is transmitted to the brain. There after the brain interprets the type of smell.
6b)
i)Shell
ii)Membranes
iii)Airspace
iv)Albumen
v)Yolk
vi)Chalaza
6ci)
autotrophs are organisms that can synthesizes food from inorganic substances by using chemical energy or light
6cii)
i)Bacteria
ii)Unicellular algae
6d)
i)providing leadership on matters critical to health
ii)shaping the research agenda and stimulating the generation
iii)translation and dissemination of valuable knowledge
iv)setting norms and standards
v)promoting and monitoring their implementation
6e)
i)plants: Water Wisteria and Java Moss.
ii)Animals: catfish and earthworm
6f)
In tabular form
-Mammalian skin-
i)It has melanin
ii)It has sweat pores
iii)Does not show photosynthesis
iv)It composes of animal cells
v)It is touch receptive
-Plant epidermis-
i)It has chlorophyll
ii)It has stomata
iii)It shows photosynthesis
iv)It is composed of plant cells
v)It is not touch receptive
6gi)
i)Intra specific competition
6gii)
i)Inter specific competition
[: 2a)
i)They catalyse reactions by lowering the activation energy of a reaction
ii)They are regenerated after each reaction
iii)They are substrate specific, hence only molecules which are complementary to their shape can bind to it.
iv)They aid in metabolism(anabolism and catabolism)
2bi)
-Pancreatic lipase
-Amylase
2bii)
i)maltae act
ii)lipase act
2bii)
i)it converts fat and oil to fatty acids and glycerol
ii)it converts starch to maltose
2ci)
Chlorophyll is necessary to absorb the radiant energy of the sun to synthesize sugar during photosynthesis
2cii)
i)Magnessium
ii)Iron
2ciii)
i)Magnessium ---}Yellowing of leaves and poor growth
ii)Iron---}Yellowing of leaves and poor growth
[ 2D) Procedures
Remove a green leaf from a plant that has been exposed to sunlight for a few hours
Half-fill a 250cm3 beaker with water. Heat the water until it boils. Keep the water at boiling point.
Use the forceps to place the leaf in the boiling water. Boil for 2 minutes.
Turn off the Bunsen Burner. (If you are using a heat source without a naked flame - electric water bath or hot plate - this step is unnecessary.)
Place the boiled leaf in a boiling tube containing 90% ethanol.
Place the boiling tube in hot water and boil for 10 minutes or until the leaf decolourizes. ( It may be necessary to replace the ethanol)
Gently remove the leaf and wash with a fine trickle of cold tap water.
Spread the leaf evenly on a white tile.
Add a few drops of iodine/potassium iodide solution to the leaf and note any observations.
Observations/Results
The leaf was flaccid (soft) after being boiled in water
The ethanol changed from colorless to green
The leaf was brittle after being boiled in ethanol
The leaf become flaccid once more after being rinsed in cold water
After iodine solution was added...
OBSERVATIONS
No color change (Iodine Solution remains brown)
Iodine/Potassium Iodide solution changed from brown to blue- black
INTERPRETATION
Starch is not present
Starch is present
