In sunflowers, tall stems are dominant (S) over short stems. If the stem

The _____ passively diffuses oxygen and carbon dioxide in and out of the cell.

polet [3.4K]

The _____ passively diffuses oxygen and carbon dioxide in and out of the cell.Through the plasma membrane, oxygen and carbon dioxide diffuses passively.
However, it is thru a transport that they in act to diffuse, -concentration gradient.

3 0

3 years ago

You are studying a biochemical pathway in the mold Neurospora where enzyme 1 converts the initial substrate into intermediate su

solmaris [256]

Complete question:

You are studying a biochemical pathway in the mold Neurospora where enzyme 1 converts the initial substrate into intermediate substrate A; enzyme 2 converts intermediate substrate A into intermediate substrate B; enzyme 3 converts intermediate substrate B into intermediate substrate C; and enzyme 4 converts intermediate substrate C into the end product, an amino acid that is essential for growth. You isolate a mutant that is unable to grow on minimal media. Which data would provide the strongest support for the hypothesis that this mutation occurred in the gene that codes for enzyme 2?

a. The mold can grow on rich medium plus intermediate substrate C, but not on rich medium plus intermediate substrate B.

b. The mold can grow on minimal medium plus intermediate substrate B, but not on minimal medium plus the initial substrate.

c. The mold can grow on minimal medium plus intermediate substrate B, but not on minimal medium plus intermediate substrate A.

d. The mold can grow on rich medium plus intermediate substrate D, but not on rich medium plus intermediate substrate C.

e. The mold can grow on minimal medium plus intermediate substrate A, but not on minimal medium plus intermediate substrate C.

Answer:

c. The mold can grow on minimal medium plus intermediate substrate B, but not on minimal medium plus intermediate substrate A.

Explanation:

Let us first diagram the pathway for a better understanding.

The normal organism produces four enzymes that convert substrates in the medium that allow it to survive, grow, and reproduce.

initial substrate ------------> A ----------------> B ----------------> C ----------------> AA

Enzyme 1 Enzyme 2 Enzyme 3 Enzyme 4

Any mutation on the Neurospora´s enzymes will not let the organism grow on the minimal medium because it will not be able to convert the minimal substrate into the following one, because the mutated enzyme will not accomplish its original function.

So if the mutation occurs in enzyme 1, the organism will not be able to convert the initial substrate into intermediate substrate A. And the rest of the reaction will not be possible either because of the lack of substance A.

initial substrate -----X----> A -------X-----> B ------X--------> C ------X-------> AA

mutated Enzyme 1  Enzyme 2 Enzyme 3 Enzyme 4

If the mutation occurs in enzyme 2, the organism will not be able to convert the intermediate substrate A into intermediate substrate B. And the rest of the reaction will not be possible either because of the lack of substance B.

initial substrate ------------> A -------X--------> B -------X------> C --------X-----> AA

Enzyme 1 mutated Enz. 2 Enzyme 3 Enzyme 4

If the mutation occurs in enzyme 3, the organism will not be able to convert the intermediate substrate B into intermediate substrate C. And the last reaction will not be possible either because of the lack of substance C.

initial substrate ------------> A ----------------> B -------X--------> C -------X------> AA

Enzyme 1 Enzyme 2 mutated Enz. 3 Enzyme 4

And if the mutation occurs in enzyme 4, the organism will not be able to convert the intermediate substrate C into the essential amino acid.

initial substrate ------------> A ----------------> B ----------------> C -------X-------> AA

Enzyme 1 Enzyme 2 Enzyme 3 Mutated Enz. 4

But, if we artificially add to the medium the substrate that should be produced by the original enzyme (and that is not converted because of the mutation), then the organism will grow and survive because the other enzymes will be able to produce the essential amino acid.

So, if enzyme 2 is the only enzyme mutated, the organism will not be able to live in a medium with substrate A because the mutated enzyme will not convert the substrate A into B. There will not be B substrate in the medium, and the other enzymes will not produce the essential amino acid. So if the mutation occurs in enzyme 2, substrate A is useless to the organism because it will not survive.

But if we add the intermediate substrate B to the medium, the organism will survive. In a medium with substrate B, all the other reactions will be possible, and the organism will get the essential amino acid. The artificial addition of B substrate will replace the function of the original enzyme 2 -which is the one that converts A into B-.

3 0

3 years ago

Drag the terms to their correct locations in this concept map about evolution. ResetHelp living speciesliving species diversityd

Taya2010 [7]

Answer:

a) diversity

b) natural selection

c) living species

d) ancestral species

e) heritable variations in a population

f) greater reproductive success

g) an evolutionary adaptation

Darwin proposed a mechanism for evolution: natural selection, in which heritable traits that help organisms survive and reproduce become more common in a population over time.

See attached picture

6 0

3 years ago

Watch the video “Teen Stress.” Now, imagine that a friend confides in you that he is going to the doctor because he feels that s

vfiekz [6]

Answer:

questions:

Should I or can I eat salty foods?

Do I have to check my pressure immediately?

Do I have to follow a balanced diet?

Is it good to do physical activity?

Do I have to worry about the signs of eye flickering and headache?

Explanation:

Blood pressure is regulated by endogenous mechanisms, although these sometimes fail and it is necessary to take drugs to reduce high blood pressure, an example of which is beta-blockers.

Blood pressure is also regulated by diets based on low sodium consumption, necessary calories and with great contributions of nutrients since cardiac or cardiovascular health is also essential in the face of possible formation of atheroma plaques.

The increase in blood pressure with the appearance of atheroma plaques is very common, and it is also the two most frequent causes of AMI (acute myocardial infarction)

4 0

4 years ago

Read 2 more answers

A star appears to be red in the night sky. Is the star traveling toward the earth or away from the earth? How do we know this? (

neonofarm [45]

Answer:

The star is travelling away from the earth.

Explanation:

A star’s temperature largely determines its color. Stars with higher temperature have a bluish color and stars with low temperature appear red in color. But the color of star that we observe from the earth is different from its actual color.

This variation in color is due to Doppler effect. When the movement of a star is towards the earth the frequency shifts to the higher frequency region and when the movement is away from the earth the frequency of the light emitted will shift to the lower frequency region. Color of light depends on the frequency. 

The color corresponding to the lower frequency region is red and color corresponding to high frequency region is blue. So when the star moves away from the earth it appears red in color.

7 0

3 years ago