Volume = (sqrt(3) / 4) · h · b<span>2</span>
<span>Muscle cells and nerve cells (neurons) are two very different types of cells. While nerve cells are involved in the transmission of neural synapses (hence the name), myocytes contract to move the skeletal bones and move the body. Muscle cells can be smooth (visceral), cardiac, or skeletal.</span><span>Oct</span>
Answer:
The correct answer is a mantle.
Explanation:
A mantle refers to an essential component of the body of molluscs. It refers to a delicate covering produced from the body wall that at certain occasions get strengthened by calcium carbonate.
In various species of molluscs, the epidermis of the mantle discharges calcium carbonate and produces a shell over the entire body. The mantle encloses the stomach, heart, gonads, and intestines of the molluscs.
Answer:
C. The basic effect of the cholera toxin is signal amplification.
Explanation:
Cholera toxin can cause its symptoms by amplifying the signals responsible for intestinal electrolyte transport through the following process:
The toxin binds to a membrane ganglioside (a phospholipid with carbohydrate residues) in the secretory cells in the small intestine. After that, a toxin subunit penetrates the cell, causing permanent activation of a G protein.
G protein activates adenylate cyclase, which catalyzes the formation of cAMP (A type of secondary messenger, important in signal transduction in cells), responsible for activating protein kinases.
Proteins undergo phosphorylation, this process amplifies chloride ions (Cl⁻) secretion.
The flow of negatively charged chloride ions out of the cell causes positively charged sodium ions to follow them in the flow.
Then water follows the electrolytes to the lumen of the small intestine by osmosis, resulting in severe diarrhea.
The answer is called heat energy. Hope this helps.