Answer:
The correct answer is option d) age of either or both parents.
Explanation:
Genetic variation is the difference in nucleotide sequences between individuals organisms within a particular population. Variation can occur either in germ cells that are sperm and egg or in somatic cells or in both.
Random fertilization of egg and sperm can lead to genetic variation is every germ cell has a different set of chromosomes. Independent assortment of chromosomes is also the same as random fertilization as it is also random. Crossing over of homologous chromosomes is one of a major source of the genetic variation as it forms a new set of chromosomes.
Thus, the correct answer is option D) age of either or both parents.
C. Amino Acids.
Proteins consist of strands of amino acids, which is produced in the ribosomes of the cell.
Answer:
My answer is the CNS consist of the brain and the spinal cord nerves but not cerebellum.
Answer: The theory of cheek cells is used for the identification of cheek cells.
Explanation:
The cells of cheek do not have cell wall. They have a cell membrane which allows on certain molecules to pass through it. The nucleus is located centrally in the cheek cells and it stores the DNA. It can be stained with the help of the methylene blue reagent. It appears blue in color which can be observed under the microscope. The cheek cells can be isolated from the buccal cavity by using cotton buds and cotton swabs can help in isolating the cells.