Question:All known organisms use genetic information to produce protein molecules via the same genetic code. This finding strongly supports the hypothesis that __________.
a) the earliest macromolecules probably arose when lightning struck an oxygen-free atmosphere
b) all organisms are descended from one or a few common ancestors
c) the genetic code readily evolves by natural selection
d) there's only one possible way to encode information in a macromolecule
Answer:
b) all organisms are descended from one or a few common ancestors
Explanation:
Protein synthesis occurs when the nucleotide sequence of the mRNA is read in the form of genetic codes. A specific genetic code specifies the same amino acid in all living beings. For example, the code "UUU" codes for phenylalanine in all the living beings irrespective of their species. This suggests that all the life forms have originated from one or few common ancestors and the genetic code has been preserved during the course of evolution of various species.
Answer:
Geography affects the weather in many ways. ... Topographical features like mountains affect the weather mostly in the way that they direct air currents. For example, air is forced to rise over mountains. Moist air will cool as it rises, and then the clouds release the water, causing precipitation like rain or snow.
Explanation:
base on research.. hope it helps
1) B
(I'm not so sure of this one) All of the other options have a steady impact on population regardless of the density of organisms except competition
2) D
Increased carbon dioxide levels would not hinder plant growth, and tsunamis aren't really linked to carbon dioxide levels. Increased carbon dioxide is unlikely to lower the air temperature so only D is left.
3) A
4) Three properties of water that allow it to sustain life are that it is adhesive, it is a good solvent, and cohesion. Adhesion is important in situations such as water travelling up xylem tubes in plants so that the water is not pulled down by gravity and can reach parts of the plant that need water. Cohesion allows the water being pulled up the xylem to stay together and for water molecules to be pulled when a neighbouring one is moved. Water being a good solvent allows inorganic minerals to be taken with water through vascular tissue, such as in the previous example.
Check on google they will give you the answer and others descriptions
Based on the CDC guidelines a person with a CD4+ cell count between 200-400 is regarded as being in <u>the second stage</u> of the HIV infection.
Acquired Immunodeficiency Syndrome
Acquired immunodeficiency syndrome (AIDS) is a condition caused by HIV (human immunodeficiency virus). AIDS is a chronic disorder and can become life-threatening for the infected person. The HIV viruses reproduce inside the host and while doing so they destroy the CD4+ immune cells which reduce the person's ability to fight against other diseases.
CD4+ cell count and AIDS
According to the CDC (U.S. Centers for Disease Control and Prevention), HIV infection is categorized into different stages based on the number of CD4+ cells.
- Stage 1: - CD4+ cell count is more than 500 per microlitre. There are no symptoms or AIDS-related conditions.
- Stage 2: - CD4+ cell count is more than 500 per microlitre. There are no symptoms or AIDS-related conditions.
- Stage 3: - The CD4+ cell count falls below 200 and AIDS-related symptoms and conditions are present.
Learn more about HIV infection here:
brainly.com/question/13662165
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