Cell transport is movement of materials across cell membranes. Cell transport includes passive and active transport. Passive transport does not require energy whereas active transport requires energy to proceed. Passive transport proceeds through diffusion, facilitated diffusion and osmosis. The purpose of the transport proteins is to protect the cell's internal environment and to keep its balance of salts, nutrients, and proteins within a range that keeps the cell and the organism alive.
Answer: CHANNEL PROTEINS provide openings in the plasma membrane for substances to flow through without changing structure, and CARRIER PROTEINS allow passage of substances through the plasma membrane after undergoing a subtle change in shape.
Explanation: They are described thus:
A channel protein is a protein that allows the transport of specific substances across a cell membrane.
Carrier proteins are proteins that carry substances from one side of a biological membrane to the other. Many carrier proteins are found in a cell’s membrane, though they may also be found in the membranes of internal organelles such as the mitochondria, chloroplasts, nucleolus, and others.
The answer is A
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The answer;
A combination pill
Explanation;
Contraception entails methods that are used to prevent pregnancy. They include; hormonal methods, barrier methods and natural methods. A combination pill is a type of oral contraceptives that contain estrogen and a progestin. It keeps the ovaries of the female from releasing an egg. Different types of this pill contains different doses of estrogen and progestin.
Answer:
B. Chemical--->Mechanical
Explanation:
because the apple is made of chemical substances but the energy is transformed into a mechanical use. Pls Brainliest! It would mean a lot! ;)