Which of the following species reproduces by internal fertilization?
a) cats
(b) Toads
(c) The fish
(d) alternative b and c
Answer:
(a) Los gatos
Explanation:
Only cats are capable of internal fertilization from the given choices above.
Internal fertilization is the fusion of gametes within an organism. This process occurs during sexual reproduction within the female.
- Toads and fishes exhibit external fertilization.
- External fertilization occurs where the male sperm externally fertilizes the eggs of the female.
- This usually takes place in a moist or wet place especially water bodies. The liquid medium will transport the sperm to the egg.
In cats, the female specie takes in reproductive cells from the male during coitus and it fertilizes the her eggs to produce a zygote.
B seasonal variations in climate tend to increase with distance from the equator
Answer:
d. an immediate increase in the concentration of antibodies, followed by a slow decline.
Explanation:
The Primary Immune Response is mediated by antibodies, which are gamma globulin proteins formed by plasma cells (B lymphocytes). Plasmocyte is a differentiated B lymphocyte capable of actively secreting antibodies.
Antibodies are produced with the main function of neutralizing and eliminating an antigen that stimulated their production. This elimination process is done in various ways through complement fixation, opsionization, anaphylactic reaction (mast cell degranulation), substance neutralization, agglutination, etc.
To neutralize the antigen, the primary immune response promotes an immediate increase in antibody concentration. This is usually a quick process. This concentration usually begins to decline in a slow process, but it will vary depending on the antigen.
The main difference between aerobic respiration and anaerobic respiration is that aerobic using oxygen in the reaction, while anaerobic does not.
Even though both aerobic and anaerobic respiration releases energy, but their reactants and other products are completely different.
For example in human, in aerobic respiration, oxygen and glucose reacts to give out carbon dioxide and water; while in anaerobic respiration, which usually happens during exercise when oxygen is not enough, the muscle cells uses only glucose to produce energy and lactic acid.
Therefore, the main difference is where aerobic uses oxygen, and anaerobic don’t.
Answer: A
Explanation: A stream terrace basically forms through this process– Temporary base level is eliminated; the stream downcuts upstream from the old temporary base level, and the former floodplain is left well above the present elevation of the stream.
