What are benefits of using tissue cultures to study medications used for treating cancer cells

Which of the following statements about ATP-powered pumps is NOT true? All ATP-powered pumps contain at least one transmembrane

MAVERICK [17]

Answer:

Only P-, F-, and V-class pumps transport ions.

Explanation:

The distinct classes of ATPases include:

1) Only the P-type ATPase actively transports ions across biological membranes. P-ATPases (also named E1-E2 ATPases) are found both in plasma and organelle membranes. These ATPases serve to transport ions and phospholipids by hydrolyzing ATP to ADP and phosphate.

2) A- and F-ATPases synthesize ATP by transforming the energy from a gradient of ions across the cell membrane.

3) V-ATPase (also known as Vacuolar-H+ ATPases) acidifies vacuole, lysosome, endosome and Golgi membranes. This type of ATPase couples the hydrolysis of ATP to the active transport of protons across biological membranes.

4) E-ATPases hydrolyze extracellular ATP.

5 0

3 years ago

You do things to keep your body in balance every day. What things do you try to keep balanced in your everyday life?

olga nikolaevna [1]

Answer:

Stretches, Exercise, run 30 mins a day, eat healthy food like apples strawberries, drink water ,and sleep at the best time of the day around 9:30 or 10:26 pm

8 0

3 years ago

If A/A ⋅ B/B is crossed with a/a ⋅ b/b and the F1 is testcrossed, what percentage of the testcross progeny will be a/a ⋅ b/b if

Alex787 [66]

Answer:

a) 25%; b) 50%; c) 45%; d) 38%

Explanation:

<h3 /><h3>a) Unlinked genes</h3>

A/A B/B X a/a b/b

F1: A/a B/b

Testcross A/a B/b X a/a b/b

The homozygous recessive individual only produces <em>ab</em><em> </em>gametes.

The F1 produces four types of gametes (each of them with a frequency of 1/4): <em>AB</em>, <em>Ab</em>, <em>aB </em>and <em>ab</em>.

25% of the progeny will be a/a b/b.

<h3>b) Completely linked genes</h3>

AB/AB X ab/ab

F1: AB/ab

Testcross AB/ab X ab/ab

The F1 produces only two types of gametes, the parentals (each of them with a frequency of 1/2): <em>AB</em> and <em>ab</em>.

50% of the progeny will be ab/ab.

<h3>c) 10 m.u. apart</h3>

AB/AB X ab/ab

F1: AB/ab

Testcross AB/ab X ab/ab

The F1 produces four types of gametes, the parentals <em>AB</em> and <em>ab </em>and the recombinants <em>Ab</em> and <em>aB</em>.

Since the genes are 10mu apart, 10% of the produced gametes will be recombinant and 90% will be parentals. Since there are two types of parental gametes, each of them has a frequency of 45%.

45% of the progeny will be ab/ab.

<h3>d) 24 m.u. apart</h3>

This is very similar to c).

Since the genes are 24mu apart, 24% of the produced gametes will be recombinant and 76% will be parentals. Since there are two types of parental gametes, each of them has a frequency of 38%.

38% of the progeny will be ab/ab.

5 0

3 years ago

If female ants can reproduce why do they need a Queen?

Pie

Answer:

Queen ants have two main responsibilities first, Queens are the founders of all ants colonies. A queen and will leave the colony she was born into a mate with flying male ants. After mating, she will scurry off to find a new location for her nest, lose her wings and lay her first hatch of eggs.

3 0

2 years ago

Before the presence of living organisms earth was a very different place match each fact about about Precambrian earth to the sp

Stolb23 [73]

The correct matches are:

- Atmosphere - Oxygen spilled into this sphere from ocean waters;

The majority of the oxygen in thee Precambrian Earth was not in the atmosphere, but instead it was in the ocean waters. With the emergence of life, large portions of this oxygen went into the atmosphere as it was released as a waste product.

- Biosphere - Cyanobacteria started to emerge as a life form;

The cyanobacteria were one of the earliest life forms. They were producers, and started to use the process of photosynthesis in order to produce food. The usage of this process caused lot of changes on the Earth later on.

- Hydrosphere - Oceans contained far less salt than they do today;

The rocks and minerals in the Precambrian Earth were not weathering and eroding in the manner they are now. Instead they were kept compact for much longer periods, influencing the mixture of of different components with the water as well in meantime.

- Lithosphere - Oxidation in rocks and minerals was not possible;

Because there was way to small amount of oxygen in the atmosphere, very close to 0%, the oxidation of rocks and minerals was not possible, as the oxygen is the gas that causes this process.

6 0

3 years ago