Answer:
Homologous pairs of chromosomes are lined up independently of other such pairs during <u>metaphase I.</u>
Explanation:
Meiosis is a special type of nuclear division that occurs only in organisms with sexual reproduction. The meyotic division gives rise to gametes.
The division begins just after the chromosome DNA has replicated in the S phase. Each chromosome is made up of two identical sister chromatids joined by their centromere. However, chromosomes are not kept separate in the nucleus, but instead bind to their homologous partners. This union called synapse, occurs during prophase I.
In metaphase I, the pairs of chromosomes are aligned in the spindle Ecuador, that is, during this stage, the homologous pairs are aligned in the metaphase plate (which is the equatorial plane of the achromatic spindle) for separation.
During anaphase I, the members are directed to the opposite poles of the cell. Telophase I, this phase begins with the arrival of chromosomes at the poles and with the formation of a nuclear envelope around each group of chromosomes. During Profase II, the nuclear membrane (if formed during Telophase I) dissolves, and spindle fibers appear.
The first meyotic metaphase and anaphase is usually completed in a short time to give rise to the phases of the second division (metaphase II and anaphase II) , which is a mitosis during which the centromeres divide and the chromatides move towards opposite poles to become gamete chromosomes. In telophase II, cytokinesis separates cells.
Answer:
The greenhouse effect is a natural process that warms the Earth's surface.
Explanation:Greenhouse gases cause the earth to warm up
Answer:
Patau's syndrome
Explanation:
Patau's syndrome is a genetic disorder caused by one additional chromosome 13, and therefore it is an aneuploidy caused by an extra chromosome (i.e., a trisomy). Individuals with Patau's syndrome have 47 chromosomes instead of 46 in some or all their somatic cells. This syndrome seriously affects fetal development, usually resulting in miscarriage, stillbirth or in neonatal death. The incidence of this syndrome is around 1/5,000 births.
I would say C) is warmer than the north and south poles