Speciation is the adaptive divergence and gradual that leads to two different species.
Reproductive isolation results in speciation when the processes of evolutionary mechanisms, physiological and behaviours are collected.
Mechanism of reproductive isolation helps in preventing members of different species from producing offsprings. A zoologist is a classified way of reproductive isolation whereby it(zoologist) is classified to the mechanism of reproductive isolation into two categories
(i) Pre-zygotic. This one acts before fertilization or before mating when it comes to animals.
(ii) Post-zygotic. It acts after fertilization.
The mechanisms appear I species which are genetically controlled and whose geographic distribution overlaps or are separated.
This is because the GP120 protein
of the HIV virus that forms the ‘knob’ is
essential for the infection of CD4 cells
of the immune system by the virus. The glycoprotein is, therefore, a good
target for vaccines especially since the
molecule is highly conserved because most mutations in the region could be highly deleterious to the virus.
Herbicides are a broad category of pesticides that are used to get rid of undesirable plants like weeds and grasses that hinder the development and productivity of desired agricultural crops. Both 2,4-D and 2,4,5T are also known as 2,4-Dichlorophenoxyacetic acid and
- Herbicides like 2,4-D and 2,4,5-T are also referred to as auxin-type herbicides or plant growth regulators. Auxins are hormones that affect cell division and elongation in order to control cell growth.
- Auxins are required by plant cells in the proper concentration for growth and development. If auxin levels are too low, plant growth is not promoted at all, and if levels are too high, plant growth is excessively stimulated.
- Most grasses are not killed by 2,4-D and 2,4,5 T, but broadleaf weeds are. It moves to the plant's meristems after being absorbed through the leaves.
- These herbicides affect the tissues' cells, causing them to continually divide and proliferate. The plant finally dies as a result of this unchecked, unsustainable growth, which also causes stem curling and withering of the leaves.
Thus, by promoting cell division, these compounds act as herbicides.
Learn more about herbicides:
brainly.com/question/21807353
#SPJ9
Answer:
In addition to erythropoietin, red blood cell production requires adequate supplies of substrates, mainly iron, vitamin B12, folate, and heme. RBCs survive about 120 days.
Explanation:
The centrioles are at opposite poles
