Explanation:
HIV virus is an RNA virus
Species is the correct answers!!!
Answer:
A) histone coding genes
Explanation:
Histones are the proteins involved in the packing of DNA in eukaryotes. They are positively charged proteins and are not found in bacteria. To analyze the evolutionary relationship in a gene between eukaryotes and bacteria, one must choose the gene present in both of them. The tRNA, rRNA and hexokinase encoding genes are common to both bacteria and eukaryotes. Therefore, one of these genes may be chosen for the study. However, histone encoding genes are not present in the genomes of bacteria. Therefore, the study of the histone encoding gene would not be useful for the mentioned purpose.
Answer:
Neurons have stable, relatively unchanging internal environments.
Explanation:
Neurons or nerve cells is the structural and functional unit of the nervous system. Neurons consists of the dendrites, axon, cell body and different cell organelles.
The neurons have mitochondria that meets the high ATP requirement and and consume more oxygen. The network of rough endoplasmic reticulum and ribosomes produce large number of proteins in neuron. The internal environment is never stable and gets changed as the nerve impulse transmission occur through the neuron. The membrane potential of the neuron gets changed and changes its internal environment.
Thus, the correct answer is option (B).