Answer:
B.
Explanation:
most valleys are weathered by running water. Glacier can also weather these. Because of running water it will carry the weathered pieces away.
Have a nice day and give brainliest! :)
Earth has roughly surface times more atmospheric pressure than mars.
Sorry if it's wrong i tried!
Answer:
<u>d. Transport proteins within the membrane serve as a tunnel for molecules to enter the cell.
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Explanation:
Solutes are typically moved across the cell through either passive or active transport. The cells, surrounded by a bilipid layer or plasma membrane is amphiphlic- its polar, hydrophilic lipid heads face outwards, while their non-polar hydrophobic lipid tails face inwards towards each other.
While lipid-soluble molecules move across the layer easily, it is also difficult for charged and also large molecules to move across its surface, into the cell. Transmembrane channels, <u>embedded within the membrane</u>, help to maintain selective permeability as transport proteins, pores and gated channels. Simple diffusion happens as a method of passive transport in cells through plasma membranes.
The solutes travel through the plasma membrane in the process of diffusion from regions of high concentration to regions of low concentration; this occurs without the use of energy. <u>Molecules moving against their concentration require active transport mechanism to cross the membrane</u>.
Answer:
im not sure but i think its Guanacos
Explanation:
Answer:
Apoptosis also plays a key role in human development. For instance, as we saw in the introduction, your hand started out as a paddle-like block of tissue when you were an embryo. The block was “carved” into fingers by apoptosis of the cells in between the developing fingers.
Explanation:
