The study of onion root tips is widely known for the clear appearance of the stages of mitosis since the chromosomes are large and are clearly visible. They are easily stained with the stainer and are visible clearly under the electron microscope. The phase of mitosis are
Interphase
Prophase
Metaphase
Anaphase
Telophase and
Cytokinesis
Each of these phases show the different stages in which the division of one cell into two daughter cells takes place. The cytokinesis is the final phase in the mitosis cell division. This is the part of cell division process during which the cytoplasm of the cell divides into two equal parts and forms into two daughter cells.
During the cytokinesis process, the spindle apparatus partitions and transports the duplicated chromatids and moves into the cytoplasm of the dividing daughter cells. In this process a dividing structure called the cell plate is formed to distinguish the daughter cells. This cell plate later grows into a double layered cell wall which then splits the parent cell into two separate cells.
Hence the option D is the right answer
In animals and plants, there are two pairs of chromosomes - one set from a male and the other set from a female. But occasionally, the original fertilized cell doesn't quite divide correctly and more than two sets arises. The fertilized cell continues to divide with the result that all the cells have the extra set of chromosomes. This happens much oftener in plants and the plant will be sterile and can't form seeds.
Answer: It was obtained 8515 years ago
Explanation:
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) to find the rate constant:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
b) for completion of 36% of reaction
t = 8515 years
The time was 8515 years.
Answer:
double helix, which is made up of a nitrogenous base, a five-carbon sugar (deoxyribose), and a phosphate group. There are four nitrogenous bases in DNA, two purines (adenine and guanine) and two pyrimidines (cytosine and thymine).
Explanation: