<span>Answer:The blood-brain
barrier (BHE)
BHE is a barrier that's highly permeability selective and protects
the central nervous system from potential dangers like viruses, bacteria and parasytes that may be circulating int he blood. <span>It is composed of endothelial cells, astrocytes, pericytes.</span></span>
Answer:
The frequency would be stable.
Explanation:
Based on the most common symptoms of cystic fibrosis, the disease only appears on adults and elderly. This feature means that the frequency of the disease would not drop or raise because they would still reproduce and pass the allele from generation to the next, maintaining the frequency stable.
The steroids are produced by the Smooth endoplasmic reticulum.
The cells, which are involved in the secretion of the steroid molecules have an abundant number of the smooth endoplasmic reticulum, which is abbrevated as SER.
The cells present in the ovary and the testis have a large number of smooth endoplasmic reticulum. The abundant number of smoothe endoplasmic reticulum allow them to produce a large amount of steroid molecule to produce the steroid hormones estrogen and testosterone.
Hence, in this case, the ovarian cells would have a large number of SER.
Water Cycle:
1. It is stored in the ground.
2. Evaporation, transportation, precipitation
3. Runoff comes straight from precipitation. Infiltration is from the ground while run off never went in the ground.
4. It will usually end up in the same place, the ocean
5. Water levels rise, temperatures rise, CO2 in atmosphere increases
Carbon Cycle:
1. Carbon is important because it is one of the basic building blocks of life.
2. Trees, animals, grass, decomposition, combustion, fossil fuels
3. Carbon enters as photosynthesis.
4. Carbon enters water to the soil decomposition. Aquatic plants have plenty of water to work with, so their main challenge is getting enough sunlight and air.
6. By breathing in the oxygen from plants.
7. Two ways carbon return from animals into water is through cellular respiration and decomposition.
8. Combustion is when we dig up the fossil fuel and burn it, then what is left goes into the air starting the cycle again.
9. Deforestation reduces the capacity of forests to be carbon sinks.
Nitrogen Cycle:
1. Nitrogen is important because it helps us grow crops, and it produces grass for animal.
2. It comes from lightning and is named nitrogen fixation.
3. Ammonification and then transitions into nitrification and then to assimilation.
Phosphorus Cycle:
1. It forms part of life sustaining molecules like DNA and RNA.
2. Phosphorus is never found in the atmosphere.
Answer:
Oxygen.
Explanation:
Oxygen molecule that is produced in the light dependent reactions. This shutting down of linear electron flow greatly affected the production of oxygen. Photosystem II gains replacement electrons from splitting of water molecules into hydrogen ions (H+) and oxygen atoms so if the electron flow is disturbed then oxygen production is greatly affected.