Answer:
The correct order, from fastest to slowest, for the passage of molecules and ions through the cell membrane is oxygen, sodium ions, glucose (option D).
Explanation:
The plasma membrane is a lipid bilayer, with glycoproteins and membrane proteins, which constitutes a semi-permeable barrier to the passage of substances into and out of the cell.
The speed with which a substance can pass through the membrane depends on its chemical properties -hydrophilic substances pass through with greater difficulty than lipophilic ones- requiring in some cases specialized transport mechanisms. The different rates with which a substance passes depends on this.
- <em>Oxygen (O₂) </em><em>passes through simple diffusion, depending on a concentration gradient. It's the molecule that passes through the membrane the fastest.
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- <em>In second place, there would be the </em><em>Na⁺ ions</em><em> -charged atoms- that cross the membrane by facilitated diffusion, through specific ionic channels.
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- <em>The </em><em>glucose</em><em> molecule, being larger, requires the use of transport proteins, being its passage through the membrane slower with respect to oxygen or sodium.</em>
Undoubtedly, molecular weight and affinity for the plasma membrane are determining factors for the passage of molecules through the lipid bilayer.
Learn more:
Simple diffusion and active transport brainly.com/question/6420224
During the winter season, the tree branches get dormant.
<u>Explanation:</u>
As the winter season starts, many plants show very slower metabolism that is the growth of the plants become very slow.
During the winter, there is very low amount of sunlight that the plants receive and so the synthesis of chlorophyll by the plants also in very small amount, and so there is least amount of sugar to metabolize by means of a slower Photosynthesis.
These tree branches become dormant during winter season, and it is mostly covered with the scales.
Answer:
The polar bear is an animal which is prevalent in the arctic region of the world which is characterized by very cold icy climate.
They adapt to these climatic conditions by maintaining a body temperature of 37°C through its thick fur and tough skin. It also has an insulating fat layer (adipose tissues) which is very thick.
This insulation helps in keeping the animal very warm in extreme temperatures.
Answer: when bright light is present, the pupil reduces in size, or flinching when feeling threatened
Explanation: i know what reflexes are :)
Answer:The answer is A
Explanation:I have had the question before