Answer:
The right answer is D. The benthic zone
Explanation:
The limnetic and the littoral zone all get a lot of sunlight so there are a lot of plant life. The pelagic zone hosts a variety of plant species so this cannot be the correct answer. That leaves us with the benthic zone.
Benthic meaning inhabiting bottom areas or substrates. Plant life at the bottom is very scarce but there are a lot of insect species.
The answer is the first one
Answer:by being produced in the testes outside the body
Explanation: spermatogenesis is the production of male gamates,the sperm.this process occurs in the seminiferous tubules in the testes.epithelial cells produces the primary spermatocyte which divides to give a secondary spermatocyte.
The secondary spermatocyte divides to form spermatids,which differentiates to form the spermatozoons.
Testis is housed in the scrotal sac.
Sperm production is sensitive to temperature. Too high temperature can cause formation of abnormal cells . As a result the scrotal sac is located outside the body
Answer:
B. stomata.
Explanation:
Stomata are openings in the surface of the plant epidermis through which gases and water vapor pass. They are formed by two elongated cells whose shape is similar to bean grain or dumbbell depending on the species. These cells are called guard cells, and in their midst there is a slit called the ostiole.
The stomata make the exchanges between the external and internal environment of the plant. They regulate the size of the opening, so it is possible to increase or decrease the rate of perspiration of the plant.
Stomata are usually located at the bottom of the leaf, but in aquatic plants such as the water lily they are at the top and still in vertical growing plants on both sides.
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<u>mechanism:</u> the process of evoluton .
Evolution is the process by which veriety of modern organisms have descended from ancient ancestors. Evolution is responsible for both the remarkable similarities of all 0rganisms and the amazing diversity of that organisms but exactly how does it work? Fundamental of the process of evolution is genetic variation upon which selective forces can act in order for evolution to occur.
Examines the mechanisms of evolution focusing on:
•<u>Decent </u>: the genetic differences that are heritable and passed on to the next generation successfully.
• <u>mechanisms of change</u>: Mutation, migration (gene flow), genetic drift, and natural selection are act as mechanism of change .
• The random nature of genetic drift and their effects .
• How variation, differential reproduction, and heredity result in evolution natural selection
.
• How different species can affect each other's evolution through co-evolution.
All of these mechanisms can cause changes in the frequencies of genes produce change in in populations, and so all of them are mechanisms of evolutionary change. However, natural selection and genetic drift (genetic flow) cannot operate unless there is genetic variation among organisms.