Answer:
<u>Part A</u> : 70 secondary oocytes will be formed.
<u>Part B</u> : 70 first polar bodies will be formed.
<u>Part C</u> : 70 ootids will be formed.
Explanation:
During oogenesis growth maturation of a single oogonium produces one primary oogonium.
the primary oogonium then undergoes meiosis -1 and produces one secondary oocyte and first polar body.
The secondary oocyte then undergoes meiosis - 2 and forms an ootid and second polar body.
The ootid then differentiates into the ovum.
As in the above scenario , 70 primary oocytes are present , they undergo meiosis-1 and produces 70 secondary oocytes and 70 first polar bodies. Hence answers of part A and B is 70.
As 70 secondary oocytes are formed , they undergo meiosis -2 and forms 70 ootids which then differentiate in 70 ovums.
Answer:
You'll have to post a picture of the problem in order for me to be able to answer the question
Explanation:
Species evolve independently possibly due to geographical isolations or behavioural isolations.
Geographical isolation includes the isolation of 2 groups of the same species. Since these 2 groups live in different locations, (e.g. a volcanic eruption resulting in a barrier between one side of an ocean and another side of the ocean), they will have different selection pressures in their different environments as well (e.g. one side of the ocean may have more sunlight and thus more underwater plantations than the other side of the ocean). Natural selection will eliminate those with disadvantageous characteristics (e.g. Fishes that only eat plants and nothing else on the side of the ocean with little plantations) with unfavourable alleles, and select for those with advantageous characteristics (e.g. Fishes are able to eat plants and other organic substances as well on the side of the ocean with little plantations) with favourable alleles.
Since the 2 groups have different selection pressures, natural selection will occur in different ways, selecting for and against different types of fishes with different types of alleles. Also, because of the barrier, they are not able to mate with each other, and there are no mixing of genes from one side of the ocean and the other side. They are genetically isolated. As genetic drift occurs over time, their gene pools become different from each other. Thus, they evolve independently.
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Answer: d. All the above
Fertilizers can be deterimental to the environment. Excess use of fertilizers will result in eutrophication in the water body. Water body being more enriched with nutrients will result in excessive growth of aquatic plants. This also result in algal bloom in which algae grows on the surface of water body because of this atmospheric oxygen not able to reach the aquatic plants, hence results in oxygen depletion.