AP BIOLOGY

CELL DIVISION

CELL DIVISION AND CANCEROUS CELLS

Please wait while the activity loads.
If this activity does not load, try refreshing your browser. Also, this page requires javascript. Please visit using a browser with javascript enabled.

If loading fails, click here to try again

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]

Which of the following distinguishes prophase 1 of meiosis from prophase of mitosis?

A	Spindle forms
B	Chromosomes become visible
C	Nuclear membrane breaks down
D	Pairing of homologous chromosomes

Explanation:

Detailed explanation-1: -Homologous chromosomes pair up. Explanation: During prophase 1, it occurs chromosomes condensation. The principal difference with the mitosis prophase is that during meiosis prophase 1, each chromosome gets carefully in pair with its homologous chromosome.

Detailed explanation-2: -Pairing of homologous chromosomes does not occur in the prophase of mitosis, whereas homologous chromosomes pair up in prophase I of meiosis I. In the prophase of mitosis, recombination, and crossing over do not take place. In prophase, I of meiosis I, recombination, crossing over, and synapsis takes place.

Detailed explanation-3: -During prophase I, homologous chromosomes pair and form synapses, a step unique to meiosis. The paired chromosomes are called bivalents, and the formation of chiasmata caused by genetic recombination becomes apparent. Chromosomal condensation allows these to be viewed in the microscope.

Detailed explanation-4: -Prophase I involves the separation of homologous chromosomes while prophase II involves the separation of sister chromatids (there are no homologous chromosomes in prophase II).

There is 1 question to complete.