Answer:
The fewer number of T cells a person has, the more chances to be affected by an opportunistic infection. When the number of T cells reaches 200 cells/µl, the person is at risk of being infected by other infections.
Explanation:
The whole immune system of a person who is infected with HIV infection seems to be severely affected. When the person is not treated or the disease is in a very advanced stage, the depletion of the T- cells turns to be very sharped, especially CD4+ T cells. At this point, the immune system can not resist the attack of other microorganisms. The <em>lower is the number of CD4+ T Cells, the higher possibility the person has to be attacked by opportunistic infections. </em>
Classically, it has been suggested that opportunistic infections appear after the CD4 + T lymphocytes reach very low levels, such as 200 cells/µl. The number of circulating T cells can be used as an indicator and a measure of global "immune competence", and the previously mentioned amount of CD4 + T cells is an accepted universal reference used to predict the risk of having one of these opportunistic infections.
Our nervous system runs on chemical synapses ! that means we need chemical to transfer information from one neuron to another !
so when the signal reaches the synaptic knob of one neuron , it stimulates the neurotransmitters containing vacuoles to release the neurotransmitters !
the neurotransmitters may be dopamine, acetylcholine etc and after reaching the dendrites of other neuron, it stimulates signal in the other neuron and thus a signal travel from one part of body to other !
<h3><u>Comparison between Galapagos penguin and cold adapted Emperor penguin of Antarctica:</u></h3>
<u>Galapagos penguin:</u>
- Galapagos penguins are the only species of penguins that live north of the Equator.
- The Galapagos penguins breed all-round the year.
- The Galapagos penguins are smaller compared to the cold-adapted emperor penguins of Antarctica.
- The breeding and nesting place of the Galapagos penguins lie on the shoreline.
<u>Emperor penguin:</u>
- The emperor penguins live and adapt to the cold Antarctic environment.
- The Emperor penguins breed only during the Antarctic winters.
- The nesting of emperor penguins is on ice cliffs and icebergs where the eggs are protected from the strong and cold Antarctic winds.
- However, both of these species of penguins are at risk of extinction due to the rise in temperature and shortage of foods.
Answer: B. Melting temperatures of primer should be between 55-80 degree Celsius.
Explanation:
Bacause the melting temperature controls the binding of the primers to your template DNA. At melting temperature 50% of the primer molecules are bound to their corresponding target sequence. If the difference in melting temperature between the two primers is too high, it might be difficult to find experimental conditions where both primers can bind to their target.
Whaaat.. I don’t understand that language..
