Changes in the dna are called mutations. They can occur spontaneously. Mutations can only be passed down in gametes--sperm and egg cells. with Darwins theory at mind a mutation needs to pass the test of natural selection to remain in the gene pool. So purposly making mutation or altercations may end in diseases/illnesses or in some cases death because they body can not take it.....hope this helps if it doesnt im sorry!
Answer;
Retinohypothalamic path
A small branch of the optic nerve, known as the retinohypothalamic path extends directly from the retina to the SCN.
Explanation;
The SCN is an abbreviations for suprachiasmatic nucleus or nuclei; which is a region in the hypothalamus. that is responsible for controlling circadian rhythms.
Retinohypothalamic path is a neural input pathway that extends directly from the retina to the SCN.
Answer:
sensory neurons
Explanation:
Sensory neurons carry nerve impulses from sense organs and internal organs to the central nervous system.
Answer:
A. His mitochondria lack the transport protein that moves pyruvate across the outer mitochondrial membrane.
Explanation:
Pyruvate is from the breakdown of carbohydrates such as glucose through glycolysis. Glucose enters the cytosol through specific transporters (the GLUT family) and is processed by one of several pathways depending on cellular requirements. Glycolysis occurs in the cytosol and produces a limited amount of ATP, but the end product is two 3-carbon molecules of pyruvate, which maybe diverted again into many pathways depending on the requirements of the cell. In aerobic conditions, pyruvate is primarily transported into the mitochondrial matrix and converted to acetyl-coenzyme A (acetyl-CoA) and carbon dioxide by the pyruvate dehydrogenase complex (PDC).
Initially it was proposed that pyruvate was able to cross the membrane in its undissociated (acid) form but evaluation of its biochemical properties show that it is largely in its ionic form within the cell and should therefore require a transporter.
Transport of pyruvate across the outer mitochondrial membrane appears to be easily accomplished via large non-selective channels such as voltage-dependent anion channels/porin, which enable passive diffusion. Indeed, deficiencies in these channels have been suggested to block pyruvate metabolism
