Answer:
The mechanisms of transport across the cell membrane are as follow: 1- simple diffusion, 2- facilitated diffusion, 3- primary active transport and 4-secondary active transport
Explanation:
The cell membrane is a selectively permeable structure capable of transporting substances by different mechanisms. Simple diffusion is a type of passive transport (i.e. does not require energy) where non-polar molecules (e.g. O2, CO2) pass across the membrane by a process that does not require energy from the cell. Facilitated diffusion is another type of passive transport where larger polar molecules (e.g., glucose and amino acids) pass across the membrane by using specific transmembrane integral proteins. On the other hand, primary active transport is a type of active transport that uses chemical energy (e.g., ATP) to move substances such as metal ions (Na+, K+, Ca2+) across the cell membrane against their concentration gradient. Finally, secondary active transport is another type of active transport where transporter proteins are used to couple the movement of ions (e.g., H+ protons) down their electrochemical gradient to the transport of another ions/solutes against their concentration/ electrochemical gradient.
In psychology, the term nature refers to traits that
are a result of heredity.
<span>Plato (428–347 BC)
believed that people’s ability to think, feel and interact are innate and
natural. That is, the person already had a set of its characteristics by the
moment he or she was born through his or her genes passed on from his parents.
He believed that people already have the certain tendency to react to a certain
stimulus even before he was taught by his environment.</span>
<span>Answer D is not correct, as gymnosprems are used widely for consumer goods such as lumber, soap, and nail polish.
Answer C is not correct event though wheat and corn are two of the main foods supplied to people in the world.
Answer B is a very subjective question, because some people argue that selective breeding helps agriculture, while others do not.
The correct answer is A. The green revolution was a period of scientific discoveries that lead to an increase in the supply of food worldwide.</span>
Explanation:
Phototropism- a response to <u>light stimulus</u> that directs the stem to grow toward the light and roots to grow away from it.
ii. Gravitropism- Stems and leaves grow away from the force of <u>gravity</u> while roots grow toward it.
iii.Thigmotropism - growth in response to <u>touch stimulus.</u> The side of the stem in contact with the object grows slower than the side not in contact. This causes the vine to twist around the object.
6. C. Concentration of wind and water.
7. B. Potash
8. D. Exploring rock formations for mineralization
9. B. 30%
10. C. A longwall.
