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3 years ago

What type of molecules pass directly through the membrane? (Passive transport)

Biology

1 answer:

zepelin [54]3 years ago

4 0

Answer:

The plasma membrane is selectively permeable; hydrophobic molecules and small polar molecules can diffuse through the lipid layer, but ions and large polar molecules cannot.

ATP is an energy molecule, and when hydrolysis happens, it gets broken down to release the energy that was stored in its chemical bonds.

Explanation:

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Exposure to teratogens after organogenesis is complete may most likely result in select one:

Ivenika [448]

The teratogens can be defined as any physical, chemical, or infections agents that have the ability to penetrate the protective layers of the embryo, and affect its viability. The overall development and the development of the different organ systems might be affected because of these teratogens. When the embryo is exposed to the teratogens after the organogenesis is complete, it is most likely that the fetus will suffer from the stunted growth. When the organogenesis is complete, the organs are already formed, and hence, no severe damage can occur to them. Down's syndrome will result if the chromosomal abnormality occur in the fetus, which is not likely after the organogenesis is already complete. Any kind of severe anatomical defects are also least likely after organogenesis is completed. Therefore, the chances of having stunted growth are high.

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3 years ago

Pascal has a mental age of 15 and a chronological age of 20. Using the IQ formula from the text, Pascal’s IQ would be described

valentinak56 [21]

For the answer to the question above, I believe that Pascal’s IQ is below average.
He must have the same IQ as his age or even higher.
I hope this helps. Have a nice day!

5 0

3 years ago

How is movement of energy through aerobic cellular respiration

Alex_Xolod [135]

Cellular respiration is the process that cells use to break down food to use as an energy. Aerobic cellular respiration uses oxygen and yields many more ATP molecules than anaerobic cellular respiration, which does not use oxygen and yields only two ATP molecules.

8 0

3 years ago

Systolic blood pressure:_____________ a) is the higher number of a blood pressure reading. b) is the lower number of a blood pre

Alik [6]

Answer:

is the higher number of a blood pressure reading.

Explanation: systolic blood pressure is the higher number of a blood pressure reading and its measure in millimeter of mercury.

Systolic pressure is the amount of pressure in the arteries when contraction takes place in heart. Diastolic pressure is the pressure the heart when it relaxes. It is the lower number of blood pressure reading

When the systolic pressure is >120mm Hg and diastolic is less than 80mm Hg it is normal

120-129mm Hg and diastolic less than 80mm Hg it high and such person needs a regular medical check up

But when systolic 129-139 mmHg

and diastolic is 90mm Hg or above it means the individual is having hypertension stage 1

Above 140mm Hg is hypertension stage 2 and it is the most severe stage. It means the person is hypertensive and medical attention needs to be seek for necessary treatment as this could lead to death of such individual if not well managed.

6 0

3 years ago

The retinoblastoma protein, pRB, is a tumor-suppressor protein that controls the G1/S cell-cycle checkpoint. While pRB is presen

gladu [14]

Answer:

1. pRB phosphorylated: The cell will not remain in G1 phase i.e. it will enter S phase because pRB will be degraded.

2. pRB not phosphorylated: The cell will remain in G1 phase i.e. will not enter S phase because pRB will remain bound to E2F.

3. pRB bound to E2F: The cell will remain in G1 phase i.e. will not enter S phase.

4. pRB not bound to E2F: The cell will not remain in G1 phase i.e. it will enter S phase.

5. E2F bound to DNA: The cell will not remain in G1 phase i.e. it will enter S phase.

6. CDK4 bound to Cyclin D1: The cell will not remain in G1 phase i.e. it will enter S phase.

Explanation:

Retinoblastoma protein, pRB supresses tumor by regulating cell cycle progression in G1 phase. When a transcription factor known as E2F is bound to pRB the cell remains in G1 phase and did not proceed further to enter S phase. But as soon as pRB becomes phosphorylated, E2F becomes free and causes gene expression of cyclin E and and cyclin A which are required in progression of cell cycle from G1 phase to S phase.

Signaling involved in cell cycle progression from G1 phase to S phase.

When a cell is unstimulated, pRB is bound to E2F but G1 phase specific growth factors induce the expression of cyclin D through Ras-MAP kinase pathway.

Synthesis of cyclin D leads to the activation of CDK-4 which is a serine-threonine kinase. This kinase causes phosphorylation of pRB which results in the degradation of pRB.

Because of degradation of pRB, E2F becomes free and leads to the expression of cyclin E and and cyclin A which are S phase specific cyclins. This is how cell progresses from G1 phase to S phase.

E2F is a transcription factor which causes expression of S phase specific cyclins i.e. cyclin E and and cyclin A. So, E2F bound to DNA will result in cell cycle progression from G1 phase to S phase.

7 0

3 years ago