Answer:B
Explanation:Estrogen causes the lining to grow and thicken to prepare the uterus for pregnancy. In the middle of the cycle, an egg is released from one of the ovaries (ovulation). Following ovulation, levels of another hormone called progesterone begin to increase.
Trawling refers to the process of fishing that uses a fishing net through the sea water behind one or more boats. It is a common method of extraction of sea living resources.
It is the main cause of the degradation of the seabed which threatens the biodiversity. It kills a number of corals, sponges, fishes and the microflora on the seabed. Corals, particularly are damaged wouding the tissue and making them susceptible to infection. It also removes certain economically important sea weeds. The ocean sediments are disturbed causing the suspended solids to enter the seawater and causing turbidity affecting the penetration of sunlight. The suspended soilds can also cause growth of harmful algae causing algal blooms affecting the other biotic factors of the sea. The disturbance in the ocean sediments due to trawling causes the harmful pollutants like DDT that are trapped in the sediments reach the water column and enter the food chain of the living organisms.
Answer:
The correct answer is - A and D.
Explanation:
Genetic imprinting is DNA modifications that result in changing the expression but not the sequence. Factors That affect such changes present both within and outside the cell.
It is a result of the silencing of either maternal or paternal alleles in a pair. This occurs random and leads to phenomenon like X-inactivation. The mechanism involves methylation of the DNA to be silenced. paternal copy of UBE3A is silenced in neurons.