The function of the lac operon in E.coli is to normally block transcription of operon, but it stops functioning when lactose is present.
One molecule of Glucose produces 38 molecules of ATP through the ETC in presence of enough oxygen.
<h3><u>Explanation:</u></h3>
To know the number of ATP produced from a molecule of glucose, we need to know the total amount and the type of products produced in the 3 individual steps of an aerobic respiration.
1. <u>Glycolisis</u> - In glycolisis, one molecule of glucose is converted into two molecules of pyruvate with production of 2 ATP molecules and 2 molecules of NADH.
2. <u>Pyruvate Dehydroogenase step</u> - Two molecules of pyruvate produce a total of 2 NADH.
2. <u>Kreb's Cycle</u> - In Kreb's Cycle, two molecules of Acetyl CoA produce a total of 6 NADH, 2FADH and 2 GTP which is again equivalent to 2 ATP.
In the ETC, each NADH is converted into 3 molecules of ATP and each FADH is converted into 2 molecules of ATP.
In the whole process till now, total of 10 molecules of NADH, 2 molecules of FADH and 4 ATPs.
So total number of ATP produced is 10*3 + 2*2 + 4 = 30+4+4 =38.
Answer:
Intensity of heat, lack of water, and a blazing/searing sun.
<h2>
Why are there so few humans and animals in the desert?</h2>
A desert is defined as a place with a hot and dry temperature, little or no rainfall (less than 25 cm), a barren landscape, a lack of water, and dry soil. There is very little vegetation. Plants appear only after rain, are seasonal, and have a short lifespan. Dust storms and shifting dunes may be dangerous. In other words, the circumstances are unfit for human occupancy. That is why relatively few people live in or near deserts. Animal life is likewise sparse, yet abundant in some areas. Some locations, such as Egypt's Nile Valley, may be heavily inhabited if enough water is available. In reality, air-cooling, air-conditioning, and irrigation facilities, as well as the discovery of petroleum wherever and whenever it was accessible, have made desert life more pleasant, dynamic, and have drawn people from outside, such as the Gulf area.
<h2>Why don't desert animals just move somewhere greener?</h2>
Deserts are a result of the Earth's atmosphere. Do you notice how deserts appear to be in similar zones? This is due to the tight link between deserts and rainforests. So this is what generates a desert, not what attracts or maintains animals here. Plants bring them and keep them alive. As plants adapt, so do animals, and the desert creates a complete ecosystem. They do not depart since they have adapted to their surroundings.
Answer:
The answer is <em><u>D.
</u></em>
Explanation:
Viruses can evade the processing and presentation of antigens, for example by interfering with the expression of MHC class I proteins, although this increases their susceptibility to be detected by natural killer cells (NK). However, some members of the herpesvirus, papillomavirus, retrovirus, poxvirus and flavivirus families have also developed strategies to escape the attack of NK cells and promote their survival, inhibiting cell apoptosis. Finally, some pathogens often change surface antigens frequently, as in the case of influenza viruses (orthomyxovirus).
The human immunodeficiency virus (HIV) affects CD4 + T cells and degrades the host's ability to counterattack with a strong cell-mediated immune response. There are so many tactics of immune evasion used by HIV, which have so far hindered the development of an effective vaccine.
Answer: There are two kinds of communication in the world of living cells. Communication between cells is called intercellular signaling, and communication within a cell is called intracellular signaling. An easy way to remember the distinction is by understanding the Latin origin of the prefixes: inter– means “between” (for example, intersecting lines are those that cross each other) and intra– means “inside” (like intravenous). Chemical sign
Explanation:
