We are well aware that there are two stages of photosynthesis:
- Light dependent reactions
- Light independent reactions/ Calvin cycle/ dark reactions.
Calvin cycle or light-independent reactions:
This comprise the process during which carbon dioxide enters into the leaves of plants and passes through series of steps to form sugar or food. This process depends on the supply of ATP, (the ATP that is formed previously during light dependent reactions).
Now there are three stages of Calvin cycle:
- 1) carbon fixation
- 2) reduction
- 3) regeneration
During the process of carbon fixation CO2 combines with a 5-carbon compound called RuBP or ribulose-1,5-bisphosphate which results in the synthesis of a 6-carbon compound that splits up in to 2 three carbon compounds called phosphoglyceric acid (3-PGA).
Here out focus will be the process of Reduction.
Reduction is the second stage of Calvin cycle during which phosphoglyceric acid (3-PGA) is converted to glyceraldehyde-3-phosphate (G3P) that is a sugar. During the process of reduction, energy in the form of ATP and NADPH are used for the conversion of 3-PGA to G3P. As 3-PGA is reduced to G3P, therefore this process is known as reduction.
After reduction, a series of reactions occur that lead to the synthesis of glucose but since focus of our question was reduction, so you can see more details of the process in attached figure.
Hope it helps!
I believe the correct answer is: HIV is spread during unprotected sex or through contact with infected blood; it cannot be cured, but early treatment can minimize the long-term consequences.
<h2>Explanation:</h2>
Human Immunodeficiency Virus is a type of virus which causes an impairment of the immune system of the person making them susceptible to diseases such as tuberculosis, influenza and any other disease that can exploit this opportunity. It is spread by a person coming into direct contact with infected bodily fluids such as saliva during deep kissing, semen during intercourse, blood after an accident or even fluids when sharing needles and syringes for drug addicts. There is no cure but the current form of treatment slows down the virus to prevent some consequences.
<h2>Further Explanation:</h2>
The virus is enters the body through open wounds or surfaces such as the vagina or mouth where the skin is very thin and can tear. After penetrating the skin, it attaches to specific immune cells called CD8+ T-cells on points called receptors. It then enters the cell and replicates itself in the nucleus of the cell and as it goes out, it kills these immune cells making the person to have a weak immune system. The current drugs used called AntiRetroVirals (ARVs) such as the drug Zidovudin stops the virus from replicating thus reducing the total amount of virus in the body called the Viral Load. Some drugs target enzymes called proteases and reverse transcriptase that help the virus to replicate. This viral load is what is counted to estimate the total volume of HIV someone has in their body. Infected persons should use protection while having sex and also avoid sharing sharp objects to prevent transmission. They also need to take their medication to make them much more healthier in addition to taking proper balanced diets.
Level: High School
Subject: Biology
Topic: The Immune System
The
first observation was that, natural selection might itself be variable because
it is dependent with the different seasons the environment have. Second, the
frequency of small-beak depth Geospiza fortis became lesser on an island when a
large-beak-depth was introduced because the large-beak-depth species has
greater survival rate especially during dry season were they can eat larger and
harder seeds as compare to the small-beak-depth birds.
