Fusion and gravity
Fusion and gravity keep the sun from blowing itself up. A large amount of energy is released by the
sun. Protons are fused together to form helium atoms due to the high heat and
pressure at the center of the sun. The Sun does not blow itself up from the
outer pressure of nuclear fusion in as much as the inner force of gravity
balances it.
Answer:
D
Explanation:
A robin building a nest is not learned or taught like the others. It is just instinctive for robins to build nests.
<span>The Cerebrum: The cerebrum or cortex is the largest part of the human brain, associated with higher brain function such as thought and action. The cerebral cortex is divided into four sections, called "lobes": the frontal lobe, parietal lobe, occipital lobe, and temporal lobe.</span>
Most of the cells in the human body are diploid.
Diploid is a cell or organism that has paired chromosomes, one from each parent. In humans majority of the cells are diploid and have 23 pairs of chromosomes. The exception are the human sex cells (egg and sperm cells). These contain a single set of chromosomes and are known as haploid.
Answer: a. Genetic recombination (crossing over)
b. Can also be explained in terms of crossing over
c. Non disjunction of homologous chromosomes in meiosis 1
Explanation:
The process that allows for the transfer of both the paternal and maternal materials to is the crossing over process that takes at meiosis 1 changing them to secondary spermatocytes. While they are still primary spermatocytes, they are still diploid cells having both the maternal and paternal chromosomes. But since the spermatozoon is an haploid cell, it is able to retail some of both parents chromosome by the crossing over event which takes place between homologous paternal and maternal chromosomes allowing them to exchange materials. Thus the chromosomal contents of the primary spermatocyte differs from that of the spermatozoon.
C. This can occur as a result of the one of the homologous chromosome pair refusing to separate at meiosis 1 with one gamete containing 4 chromosomes/8 sister chromatids and the second having 2 chromosomes/4 sister chromatids.
