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
Answer:
Must be able to reproduce.
Explanation:
All organism are able to reproduce.
The right option is abnormal
menstrual cycles
The female athlete triad is a
medical condition that is seen in physically active females. The clinical manifestations
of this condition involve three components which are; menstrual dysfunction, low
energy availability with or without disordered eating and decreased bone
density. Based on the information given above, Wendy has abnormal menstrual
cycles.
The answer is Lionfish
are native to the tropical Pacific. There are no natural water routes of warm
water between the Pacific and Atlantic oceans.
Invasive species is a species that colonizes an environment
in which it is not a native species and tends to upset the natural balance of that environment. Lionfish are naturally
found in the indo-pacific, which is their
native environment. However, their presence
in the eastern United States has have threatened
the ecosystem of the region. The fish has decimated fisheries and reef
ecosystem since they also don’t have natural predators in the region. Therefore,
their population explodes unchecked.
It is true that cells spend most of their time dividing. In fact, they spend 78% of their "life" in interphase.
