PLEASE HELP BIOLOGY!!!! (15 POINTS!)

1 answer:

6 0

1. Some substances passes through small holes in the surface cell membrane. This is called diffusion and does not require cell to expend energy.In this way the passive transport occur if the cell doo not expend any energy. 2.In active transport,the particles move across the cell membrane from slower concentration to higher concentration . Active transport is the energy requiring process of pumping molecules and ions across membranes uphill against a gradient.This process uses the energy of ATP. 3. Endocytosis and Exocytosis are important mechanisms for bringing substances into and out of a cell.The vesicles fuse with the plasma membrane ,causing the contents of the vesicles to spill outside the cell.

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Public controversies may occur over a well-established scientific theory. Such controversies are particularly likely to arise wh

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Answer:

The theory given in the science requires the proof. The experimental procedure and observation must be done to make any statements as the scientific theory.

The other scientists can ask question and make controversy about the particular scientific theory. This might occur when the theory affects the moral standards are blended with the phenomena of the nature. The controversy might also occur if its effects the ethics and against the laws of nature.

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Most adults should consume no more than 30 percent of their daily calories from fat. A person on a daily diet of 2,500 calories

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750

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When it increases the pH goes down

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A cactus with long spines protects itself from animals better than a cactus with short spines. According to natural selection, _

worty [1.4K]

<span>Long-spined cacti will survive longer and reproduce more often than short-spined cacti</span>. Because natural selection suggests that organisms with certain traits that give them better chance at survival or reproductive rate will be pass on to their offspring.

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Read 2 more answers

Phenylketonuria, PKU, is a single-gene recessive human

astraxan [27]

Answer:

1/2

Explanation:

Let's assume that the allele "p" is responsible for PKU in the homozygous state. According to the given information, both the parents are unaffected by the disorder but have an affected child. This means that both the parents carry at least one copy of the recessive allele responsible for the disease. Therefore, the genotype of each of the parents is Pp. A cross between Pp and Pp would produce progeny in following ratio=

Pp x Pp = 1/4 PP: 1/2/ Pp: 1/4 pp

Therefore, the probability that their next child will carry just one recessive allele is 1/2.

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