Answer:
B) increased exchange surface provided by their membranes
Explanation:
Alveoli are tiny air sacs that are responsible for exchanging oxygen (O2) and carbon dioxide (CO2) in the lungs. Alveoli have elastic fibers in order to expand and recoil depending on the volume of air breathed in. The alveolar epithelial cells (pneumocytes) may adopt a shape that serves to increase the surface area of gas exchange. On the other hand, intestinal epithelial cells have microvilli, which are microscopic projections in the plasma membrane. Microvilli serve to increase the cell's surface area, thereby facilitating the absorption of nutrients and water.
Answer: what are the options?
Explanation:
<span>Protein channels are needed to transport substances because it accelerates the transport process. Very few substances enter or leave cells without being attached to a transport protein. Different types of substances require different types of proteins to transport them. Protein channels transport water or ions downwards and ATP-powered pumps transport molecules or ions upwards. ATP generates energy to transport the molecules upwards. Gravity is used to transport the water molecules downwards. So, in a nutshell, if substances need to be transported from the top of the body downward, the force of gravity is used to transport the substances down. If substances need to be transported upwards, ATP, a coenzyme, is used to generate energy to transport the substance upwards</span>
D. development of transgenic organisms
I believe it is 'mutagens' or 'mutagenic agents'
