Human sperm and eggs contain 23 chromosomes. Human zygotes contain 46<span> chromosomes. The type of cell division that produces gametes with half the normal chromosome number is called meiosis. It is used to produce cells for repair and asexual reproduction.</span>
Answer;
The human eye contains more rods than cones photoreceptors.
Explanation;
-The retina of the human eye is the back part of the eye that contains the cells that respond to light. These specialized cells are called photoreceptors. There are 2 types of photoreceptors in the retina: rods and cones.
-The rods are most sensitive to light and dark changes, shape and movement and contain only one type of light-sensitive pigment. Rods are more numerous than cones in the periphery of the retina. The cones are not as sensitive to light as the rods. However, cones are most sensitive to one of three different colors (green, red or blue).
Answer:
The above paragraphs describes that how salt- and fresh-water fish regulates their osmoregulation. Hence, the correct answer would be c. have adapted to deal with osmosis.
Osmosis is the process by which solvent's molecule move from region of low concentration (hypo-tonic) to the region of high concentration (hyper-tonic) through a semi-permeable membrane.
In sea-water fishes, the body fluids are hypo-tonic to the surrounding water and thus water is kept moving out of their gills. In order to prevent the excess water loss they need to drink water constantly and excrete concentrated urine.
In contrast, fresh-water fishes body fluids are hyper-tonic to surrounding water and hence, water keeps entering in their body through gills. So, in order to prevent excess dilution they absorb salt from surrounding with the help of gills and also their bodies reabsorb salt from urine.
