2ai
a gene is a sequence of DNA or RNA which codes for a molecule that has a function. During gene expression, the DNA is first copied into RNA.
2aii
Implantation: The act of setting in firmly. In embryology, implantation refers specifically to the attachment of the fertilized egg to the uterine lining, which occurs approximately 6 or 7 days after conception (fertilization).
2aiii
a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding. The species is the principal natural taxonomic unit, ranking below a genus and denoted by a Latin binomial, e.g. Homo sapiens.
2aiv
A saprophyte or saprotroph is an organism which gets its energy from dead and decaying organic matter. This may be decaying pieces of plants or animals.
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1ai)
I. Plants need sunlight for the process of photosynthesis.
ii. Plants use chlorophyll and light to make food.
1b)
i.humerus
ii.radius
iii.ulna
iv.the ball and socket shoulder joint
v. Scapula
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(2ai)
Germination of seed refers to all changes that occur when the embryo in a seed resumes its growth and development to become independent seedling.
(2aii)
The two types of germination are:
Epigeal germination
Hypogeal germination.
Epigeal germination is the type of germination in which the cotyledon is carried above the soil during germination. The plant exhibiting this type of germination are cow pea, pepper,
Hypogeal germination is the type of germination is which the cotyledon is retained in the soil during germination. Hypogeal germination is exhibited by maize, guinea corn.
(2b)
water ---- coconut, oil palm fruit,
wind ---- cotton seed and clematis
Animals --- mango, orange.
Human --- cashew, pear.
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(3ai)
Conservation can be defined as the judicious use of natural resources to ensure their availability and preserve the quality of the environment.
(3aii)
It ensures continuous source of plant nutrient.
It ensures source of water and reservoir for soil nutrient.
To ensure preservation of soil fertility
To ensure sources of raw materials for industries
To ensure medium for agriculture.{pick any four}
(3bii)
Crop rotation is a system of farming where a crop is cultivated in a piece of land in a definite sequence in such a way that a deep rooted crop succeeds a shallow feeder and the shallow feeder succeeds a legume.
(3bii)
It ensures maximal use of the soil nutrient
It helps to renew soil fertility by the activities of the leguminous crop
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4A
OSMOSIS :: a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one.
PLASMOLYSIS contraction of the protoplast of a plant cell as a result of loss of water from the cell.
Diffusion is the net movement of molecules or atoms from a region of high concentration to a region of low concentration as a result of random motion of the molecules or atom
1d.An ecosystem includes all of the living things (plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (weather, earth, sun, soil, climate, atmosphere). ..
2ai
a gene is a sequence of DNA or RNA which codes for a molecule that has a function. During gene expression, the DNA is first copied into RNA.
2aii
Implantation: The act of setting in firmly. In embryology, implantation refers specifically to the attachment of the fertilized egg to the uterine lining, which occurs approximately 6 or 7 days after conception (fertilization).
2aiii
a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding. The species is the principal natural taxonomic unit, ranking below a genus and denoted by a Latin binomial, e.g. Homo sapiens.
2aiv
A saprophyte or saprotroph is an organism which gets its energy from dead and decaying organic matter. This may be decaying pieces of plants or animals.
4ai) diffusion is defined as the process by which molecules or ion move from a region of high concentrations to a region of low concentration until they are evenly distributed
3ai)
i) Liver fibrosis
ii) hepatitis
iii)hemochromatosis
4aii) osmosis is defined as the process by which water molecules move from a region of dilute or wicker solution to stronger solution through a selectively or permeable membrane
4aiii) plasmolysis is defined as the outward movement or flow of water from a living cell when they are place in an hyoertonic solution
4bi) effect of over crowding are ;
Aggressive behavior
State of unrest
Decrease in reproductive ability
4bii) conservation of wild life are;
Indiscriminate killing of wildlife should be discouraged
Deforestation which destroy the habitat of animal should be discouraged
Killing of young developing animals should be allow