The answer is <span>a. Each gene is at the same locus on both chromosomes.
Since e</span><span>ach gene is at the same locus on both chromosomes, they are able to pair correctly before they separate in meiosis. They never produce identical phenotypes. Also, the genes and alleles on the homologous chromosomes are not identical. </span>
Answer:
B) neurons have stable, relatively unchanging internal environments.
Explanation:
Rough endoplasmic reticulum (RER) is studded with ribosomes which in turn serve as the site for protein synthesis. A cell with an extensive network of rough endoplasmic reticulum has higher rates of protein synthesis. Mitochondria are the powerhouse of cells and serve as the site for aerobic cellular respiration. A large number of ATP molecules are produced in mitochondria. Therefore, a cell with relatively many mitochondria appears to have a higher demand for ATP and higher consumption of oxygen.
A cell with higher rates of consumption of ATP and protein synthesis should be functionally active. The charge across the membrane and the internal concentration of ions such as Na+, K+ of a neuron keep on changing during the conduction of nerve impulse. Therefore, the presence of many mitochondria and RER does not indicate that the neurons maintain relatively constant internal conditions.
