The zygote, a single cell, implants its self to the uterine wall and it developes into an embyro which is a cluster of cells.
Answer:
Channel proteins and Carrier proteins
Explanation:
These are type of membrane proteins that transcend the entire length of phosphoslipid bi- layer in the plasma membrane.They facilitate the movement of ions and molecules across the walls of the plasma membranes.
Generally, substances like glucose, amino acids, are too large to pass through the phopholipid bilayers. Likewise ions of potassium, sodium calcium, because of their polarities can not pass through either. They are ferried across the phospholipid by group of protein structures called channel proteins. Some are also transported across by carrier proteins. The process by which these protein structures aided the diffusion of substances across the phospholipid bilayer is called Facilitated diffusion.
Channel proteins are pores, that are filled with water molecules with the entrance well gated. That is the entrance is controlled by part in the inner structure of the protein which can open or close the pores like a gate to control the movement of ions across it. e.g Sodium channels are gated for movement of sodium ions by voltage or ligands(chemicals) during nervous transmission to elicits action potential. Like wise Potassium channels allow diffusion of potassium ions across the phospholipid bilayers. it gates are shut when sodium channels are open; this regulate ion exchange.
Their structures are well fixed in shape , specific to the substance or ions being transported;and the rate of diffusion depends on the like hood of opening of the gate or closure.
Carrier molecules also in the membranes do not have a fixed shape, and their transport direction is determined by the direction of concentration gradients. Thus they can flip on either sides of the membranes to aid diffusion across. Their movement can be both passive and active, and the rates of diffusion depends on the number of available carrier proteins in the membrane. They are also specific to the ions they transport.And are not gated,
Therefore these two membrane integral proteins facilitate movements of substances across the phospholipild bilayers
Though the lockdown has undoubtedly had somewhat of a negative impact on certain acpects of our society, there’s no denying that our environment has seen certain benefits since we’ve tucked ourselves away in our homes. According to the Earth Observatory at NASA, satellites have detected decreased levels of air pollution as well as carbon monoxide emission. This is attributed to the closure of most industries as well as the lack of cars and other transportation on the road. Though it isn’t just the air we’re beginning to notice changes in- for the first time in a very long time, the canals in Venice are crystal clear. With fewer boats and tourists about, the water is free of pollution for the first time in centuries. With these facts in mind, I can safely say that I believe the lockdown has definitely positively benefited the environment, but it’s up to us to keep it that way once it ends.
<span>D) Daughter cells contain the same genetic information as parent cells.</span>