Immune System is the system that consists of proteins and cells.
Answer:
What best describes how transferrin is transported through the erythrocyte plasma membrane is receptor-mediated endocytosis.
Explanation:
The incorporation of transferrin across the erythrocyte membrane depends on a transferrin receptor expressed on the surface of the membrane. The specific receptor recognizes the presence of iron-charged transferrin, transferin diferrica, incorporating it into the cell by endocytosis. Once in the cytoplasm, the iron is dissociated from the transferrin.
Free transferrin is called apotransferrin. The transferrin receptor has a high affinity for transferrin di-ferrica, which facilitates its incorporation by endocytosis, and the release of apotransferrin into the extracellular space.
The other options are not correct because:
<em> A. </em><u><em>Exocytosis</em></u><em> implies the exit of substances from the cell.</em>
<em> B. </em><u><em>Pinocytosis</em></u><em> involves the invagination of the membrane to incorporate soluble substances into the cell.</em>
<em> C. </em><u><em>Phagocytosis</em></u><em> is the incorporation of solid substances by invagination of the membrane.</em>
Enzymes are used to speed up reactions. They’re also called catalysts and their main purpose is as a speed boost for reactions
Answer:
In the carbon cycle, decomposers break down dead material from plants and other organisms and release carbon dioxide into the atmosphere, where it's available to plants for photosynthesis. ... After death, decomposition releases carbon into the air, soil and water.
Explanation:
Answer choice: [C]:
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V = d / t = 1800 mi / 40 min = 180 mi / 40 min = 45 mi / min .
Which very well could be "Answer choice: [C]: 45 m/min" ; except, this answer choice may have been written incorrectly—and should read:
"45 m/min."
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Now, notice that all the answer choices given are in "meters" per (unit time—seconds or mins.
So, we need to convert:
45 mi. to "meters", or "m".
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Note the following conversions:
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1 mi. = 1750 yd
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3 ft. = 1 yd.
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1 m = 3.2 ft.
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So, 1 mi. = ? m ;
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1 mi * ( 1760 yd/ mi) * (3 ft / 1 yd) * ( 1m / 3.2 ft) = _?_ m ?
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On the "left hand side" , the units of "mi", "yd", and "ft" ; cancel to "1" ;
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and we are left with:
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[(1760 * 3)] / [(3)*(3.2)] m = (5280 / 9.6) m = 550 m .
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So, we have: 550 m / min ; which match NONE of the answer choices.
However, it is possible that choices A or B, which are given in "m/sec" (meters per second); are among the correct choices.
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So, we convert: 550 m / min to: "m / sec " ;
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( 550 m/ min)*(1 min/ 60 sec) = (550/60) m/sec = (55/6) m/ sec
= 9 1/6 m / sec .
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which is: None of the above.
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Unless the answer choices were written incorrectly.
