Channel protein is important because it is embedded in the membrane and it also covers the membrane. This is important because the channel must transport the micromolecules and ions in and out of the cell. Carrier proteins are important because the carrier must transport the molecule in and out of the cell.
Answer:
Question: Two requirements for gas exchange which are accomplished by the gills in a fish include:
1. Water flowing in opposite directions across the gill lamellae for gas exchange, in other words, respiration is experienced by the fish.
2. The fish allows water through its mouth, then forces the water to drain through the gills supporting gill lamellae, and enhancing gas exchange.
Question: How does their structure help to satisfy these requirements?
1. The rows of gill filaments with numerous folds through diffusion makes sure oxygen from the water moves from a place of more concentration to the blood of the fish which has less concentration causing the removal of carbon dioxide.
2. The large surface area of the gill means it has to maximize the low percentage of dissolved oxygen in the water compared to the higher percentage of oxygen in the air makes it possible for water to pass through the mouth and empty through the gills after the mouth is closed.
Numerous barriers can prevent sperm from reaching and fertilizing the egg, this can be that the Sperm may be defected, or lack the required number of mitochondria needed to help move the sperm. Also, if sperm had already fertilized the egg, there is a change that takes place to the membrane surrounding the egg preventing further sperm from fertilizing.
Answer:
I think that answer might be B
