Answer:
<h2>C. placing carrier proteins in the membrane.</h2>
Explanation:
If there is no barrier preventing molecules from moving molecules, then there will be large movement of molecules from an area of high concentration to an area of low concentration. This passive process is known as diffusion. The phospholipid bilayer of a cell's membrane works as a barrier to large molecules, ions, and most hydrophilic molecules. Whereas small hydrophobic molecules can pass freely through the phospholipid bilayer, other molecules and ions are transported across the cell membrane with the help of transport proteins. Some transport proteins, allowing hydrophilic molecules and ions to passively move through them and across the cell membrane.
Examples: carrier proteins and channel proteins.
Placing carrier proteins in the cell membrane will allow the molecule to reach equal concentrations on the both the sides of the membrane and maintain that way over long time. In contrast, transport proteins known as pumps will use cellular energy, usually in the form of ATP, to transport molecules.
Placing equal numbers of intracellularly directed and extracellularly directed pumps would also equalize the concentrations of a molecule long over time. Pumps are to transport molecules against their concentration gradient, such as the sodium-potassium pump continuously moves sodium ions out of a cell.
Through the use of carrier proteins, there is equalization of concentrations of a hydrophilic molecule. This equalize the numbers of molecules on the inside and outside of the cell, but the pumps would continue moving the molecule inward, eventually resulting in more molecules inside of the cell than out.
Answer:
A galaxy is a collection of millions of stars, while a solar system is a star and the planets around it.
Explanation:
You live in a solar system, we revolve around our sun and so do the other planets making up a solar system
A monocot<span> seed has an embryo with a single cotyledon, and a </span>dicot<span> seed has an embryo with two cotyledons. </span>Monocots<span> have stem vascular systems with their bundles scattered, and </span>dicots<span> have their stem vascular systems with their bundles in a ring.</span>
Photosynthesis is carried out in the chloroplasts which contain the green pigment chlorophyll. Chlorophyll is what gives plants their characteristic color and it works by capturing the energy that is in the sunlight that strikes the plant.
Photosynthesis is important to life on Earth because grass uses photosnthesis to produce glucose, which is used within the grass for growth<span>. Subsequently, organisms that consume the grass obtain energy and so on. Therefore, photosynthesis is the process through which energy enters an ecosystem.</span>
