Answer:
The earthworm's body is divided into segments. Each segment has a number of setae or very small bristles that earthworms use to help them grip the soil as they move. An earthworm moves by using two different sets of muscles. ... The earthworm uses its circular muscles to lengthen and push itself forward again.
Answer:
<h2>
Liver
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Explanation:
1. Glucagon: it control the glucose levels in the blood.
2. Glucagon is produced by the alpha cells, in the pancreas.
3. It prevent dropping of blood glucose levels too low. so, it acts on the liver in many ways:
4. It stimulates the breakdown of glycogen which is stored in the liver into glucose, which finally released into the bloodstream, this process is known as glycogenolysis.
5. It also stimulates the production of glucose from amino acid molecules and some other non carbohydrate pre-cursors, by the process known as gluconeogenesis.
Quite simple really.... The CNS actually doesn't receive as much nutrients or key components from the blood... The blood actually dumps it into the Cerebrospinal fluid. The Cerebrospinal fluid therefore is directly in contact with the brain and if you want to find an infection you take from a source as close to thing as you can.
1) Embryonic stem cells can become all cell types of the body because they are pluripotent (that means having the ability to originate almost every type of cell in the body). On the other hand, adult stem cells are more limited and can only differentiate into different cell types of the same tissue. For example, if the tissue is skin, they would differentiate in keratinocytes, melanocytes, etc. We can say that adult stem cells are multipotent because they can become more than one type of cell.
1.1
Advantages of embryonic stem cells:
-They can grow easily in culture
-Originate almost every type of cell in the body with the right stimuli
Advantages of adult stem cells:
-Adult stem cells that come from this patient and then are reintroduced in him are less likely to initiate rejection after transplantation.
- They are present in a lot of tissues/organs: bone marrow, brain, blood vessels, muscle, skin, heart, and many more.
1.2 Disadvantages of embryonic stem cells:
- They are obtained from human embryos and because of that they are destroyed during the process
-There is not enough information obtained to understand this cells completely.
Disadvantages of adult stem cells:
-It's difficult to isolate these cells from the rest of the tissue
It'sts not easy to have a big number of them in cell culture
(these are a problem because it needs to exist large numbers of these cells to be used in replacement therapy for this patient.)
2)
<span>The answer is: During differentiation, certain genes are activated to produce proteins that enable specific functions.
</span>During the differentiation process, some parts of the cell genome will be activated or expressed, while others parts will have it repressed. The part that was activated will lead to translated proteins that will help dictate the shape of the cell as well as their function. This is a process of gene expression and can be activated or repressed by stimuli from the inside or outside of the cell.
3. The answer that BEST explains is Meiosis results in offspring with genotypes that are not exact copies of the parents.
Something that differentiates meiosis from mitosis is the fact that the new cells have different genetic information due to the recombination of genetic material from the parents. This will make the offspring different from the parents. Also, a process that helps mixing the DNA is Crossing over. Crossing over. is an exchange of DNA between homologous chromosomes (half are from the mother and the other half from the father).
Answer:
The correct answer is option c "Proteins that are excreted by prokaryotes are synthesized on ribosomes that are bound to the cytoplasmic surface of the plasma membrane".
Explanation:
Many prokaryotes secrete proteins, particularly, extracellular enzymes that have a function outside the cells and toxins that are not needed by the cell. As any other protein, proteins that are excreted by prokaryotes are synthesized on ribosomes that are bound to the cytoplasmic surface of the plasma membrane. However, excreted proteins go to the general secretion (Sec) pathway, where they are tagged and further processed.
