Living organisms obtain many of their requirements by diffusion. They also get rid of many of waste materials in this way. For example, Plants need carbon dioxide for photosynthesis. This diffuses from the air into the leaves through the stomata. It does this because there is a lower concentration of carbon dioxide inside the leaf as the cells are using it up. Outside the leaf in the air, there is a higher concentration. Carbon dioxide molecules therefore diffuse into the leaf down this concentration gradient :)
I hope u understood!
Answer:
c: the use of energy released from an exergonic reaction to drive an endergonic reaction.
Explanation:
<em>Energy coupling is a process involving two reactions whereby one of the reactions generate energy, and the generated energy is used to drive the other reaction. </em>
A reaction during which energy is generated is referred to as exergonic reaction while one in which energy is consumed is known as endergonic reaction. Hence, energy coupling can also be viewed as a process linking exergonic and endergonic reactions whereby the energy released in the former is used up by the latter.
A good example is illustrated by the light dependent and light independent reactions of photosynthesis during which the ATP and NADPH produced during the light dependent reaction is used to fix carbon dioxide in the light independent reaction.
<em>The correct answer is C.</em>
Well for starters, producers are living organisms that produce their own food. Like plants. And plants ironically provide us humans with oxygen as they live off of the carbon dioxide we produce. Some plants are also main vegetables that we eat, so put simply, a world without producers would be practically oxygen-less and vegetable-less.
Answer and Explanation:
Cyclins and cyclin-dependent protein kinases (CDPKs, cell proteins) also function to control the cell cycle. A group of cyclins: the G1 cyclins, are synthesized during G1 phase and function to activate CDPKs which initiate DNA synthesis at the G1/S checkpoint. The cell fails to progress to S phase if there is no sufficient synthesis of G1 cyclins. After a cell passes through this point, the G1 cyclins are degraded, allowing for another group of cyclins: the M cyclins (mitotic cyclins) to be synthesized. M cyclins activate a second group of CDPKs which allow the cell to pass the G2/M control point and into mitosis.
In the G1/s check point, entrance into the S phase is blocked if the genome is damaged. In the G2/M check point, entrance into the M phase is halted if the DNA replication is incomplete. In the M phase, anaphase blocked if chromatids are not properly assembled.
