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:
The third sentence is not correct. The correct statement would be as follows:
because the contents of the lumen of ER (or any other compartment) in the secretory or endocytic pathways never mix with the cytosol, Proteins that enter these pathways is never imported again.
Explanation:
During mitosis, specifically during prophase, when the nuclear envelope breaks down, or in other words, retracts from the chromatin, its content that is the membrane protein intermix with the ER membrane protein. However its content will always remain separated from that of the cytosol because of the presence of an intact membrane.
Answer:
The food chain showing seven organisms can be drawn as follows:
Plants → grasshoppers → mice → frog → snakes→ eagles → decomposers
The plants are the primary source of food in a food chain or a food web. The animals which feed on plants will be termed as herbivores or primary consumers like the grasshopper. The organisms feeding on primary consumers will be the secondary consumers like mice.
An energy pyramid for three of the organisms can be shown as follows:
mice (10 kilocalories)
↑
Grasshoppers (100 kilocalories)
↑
Plants ( 1000 kilocalories)
As the energy pyramid shows, only about 10% of the energy travels from one trophic level to another.
Explanation:
Answer:
Under cold water
Explanation:
This is how me and my family thaw beef
