Answer:
Immediately following the arrival of the stimulus at the axon terminal there is a short period called the latent period.
Explanation:
When a stimulus reaches the terminal of an axon, a period known as the latent period begins. This period has a short duration and during it it is possible to observe the blockage of new stimuli in the nerve fiber. Thus, the new stimuli fail to trigger an impulse and no muscle tension to be observed.
While the latent period is not finished, the neurotransmitter is released through the action of exocytosis that moves until it gets access to the receptor capable of activating the muscle cell.
The answer is letter C. |
<span>
Slight differences in the color of feathers in
birds are the result of mutations. Mutation is process that occurs through a
long period of time. It is a process in which the genes’ structures changes
thus altering the physical characteristics and behaviors of species. This
results into variant forms that may be transmitted to the next generations of
species. Mutation is caused by an alteration of single base units in DNA, or
the deletion, insertion, or rearrangement of larger sections of the genes or
chromosomes. </span>
Answer:
Internal Fertilization: Mammals,birds and reptiles in them the mode of fertilization is internal
External Fertilization: Amphibians and fishes used external fertilization.
Egg laying Animals;Birds,reptiles and some mammals platypus lays eggs.
Explanation:
Fertilization is a process in which a female egg (Ovum) and male egg (sperm) unite to form a zygote.A zygote is a fertilized egg which grows within an embryo.The process of fertilization is important in eukaryotes such as animals, humans,birds and plants. Fertilization divides a cell into many daughter cells by the process of mitosis and meiosis.It doubles the chromosome numbers.Fertilization are of two types internal and external.