The list that is composed of substances that are widely used for many years without apparent ill effects is the GRAS. GRAS is an abbreviation for generally recognized as safe; it is an American food and drug adminstration designation where chemical or substance added to food is considered safe by experts, and therefore, it is exempted from the usual federal food, drug, and cosmetic Act.
Answer:
Because of recombination and independent assortment in meiosis, each gamete contains a different set of DNA. This produces a unique combination of genes in the resulting zygote. Recombination or crossing over occurs during prophase
Answer:
The heart and lungs contain cells that contain the same information but they do different specialized functions
Explanation:
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.
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Simple diffusion and active transport brainly.com/question/6420224
