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
<span>The nurse must instruct the client to take the
medication with meal or snack to prevent stomach ulcer and to avoid lying down
for 4-5 hours after taking the drug to prevent supine hypertension. In
addition, onset of headache should be reported and blood pressure should be
constantly monitored.</span>
Highly porous and permeable
Explanation:
Compared to other types of rock layers, an aquifer is highly porous and permeable.
Aquifers are always the target when prospecting for ground water in a formation.
- Porosity is the amount of void spaces in a rock.
- Aquifers are highly porous .
- Permeability is the inter-connectivity of the void spaces and their ability to transmit fluids.
- Aquifers have very high permeability compared to other rock types.
In terms of permeability and porosity, an aquifer is higher porous and permeable.
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Biogeochemical cycle brainly.com/question/3509510
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A possible reason for the transition of algae from unicellularity
to multicellularity would be the evolution of multicellularity allowed algae to
develop traits that keep them close to the land and thus a source of nutrients.
The correct answer between all the choices given is the last choice. I
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