<span>A population's growth is strongly influenced by the proportions of individuals in different age brackets, which in turn is influenced by economic development.</span>
Permanent tissue is composed of cells that have lost the ability to divide and has attained a definite shape or form.
There are three main types of permanent tissue. 1) simple, 2)complex, 3) special tissues.
Answer:
a. parasitism:
The parasite benefits by harming the host e.g hookworms and humans
b. commensalism
In this association, one species benefits while the other is unaffected (its not harm and dies not benefit) e.g. epiphytic orchids and trees
c. mutualism
Here, both species benefit as seen in rumen bacteria and cows
Explanation:
Parasitism = +/- relationship
The predator benefits by harming the host. E.g. hookworms and humans. The hookworm (parasite) eat man blood while man (host) loses blood to it.
Commensalism = +/0 relationship
One specie(s) benefits while the other specie(s) neither benefits nor is harmed. E.g. epiphytic orchids live on tree branches or tree trunks as it's habitat or shelter while the trees neither benefits nor is harmed
Mutualism = +/+ relationship
Both organisms benefit in this relationship. E.g. rumen microbes aids grass digestion in cows, while the microbes benefit as it obtain steady food or nutrient from the cow
B). It was produced from photosynthesis
To send information from the brain or spinal cord to muscles and glands - is the purpose of motor neuron
Explanation:
As part of the central nervous system (CNS), the motor neurons connect the brain and spinal cord to all the muscles and glands present all over the body and innervates them.
Their main function is to transmit nerve impulses from the CNS to the muscles, both skeletal and smooth, and directly controls the movements of the muscles of the body.
A motor neuron is a typical nerve cell with multipolar body. It can be upper of lower motor neuron.
Right from snapping of fingers to movements of hamstrings, all muscular movements functions due to impulse carried by the motor neurons.
Degeneration of the motor neurons leads to neurodegenerative diseases like spinal muscular atrophy or amyotrophic lateral sclerosis.
