Answer:
Explanation:
The main function of the plasma membrane is to protect the cell from its surroundings. Made of a phospholipid bilayer with embedded proteins, the plasma membrane is selectively permeable to ions and organic molecules it also regulates the movement of substances in and out of cells. Plasma membranes must be very flexible in order to allow certain cells, such as red blood cells and white blood cells, to change shape as they pass through narrow capillaries. Membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors, which then trigger intracellular responses. Some viruses, such as Human Immunodeficiency Virus (HIV), can intercept these receptors to get into the cells, causing infections.
Answer:
It enters the citric acid cycle and associates with a 4-carbon molecule, forming citric acid, and then through redox reactions regenerates the 4-carbon molecule.
Explanation:
Acetyl-CoA(2C) associates with oxalacetate(4C) to form citric acid(6C). Then through redox reactions, CO2 molecules result from decarboxylation (COOH becomes R-(R1)CH-R2). And through dehydrogenation H2 molecules are incorporated in NADH+ in FADH2, resulting in the 4-carbon molecule at the beginning (oxalacetate). That's why it's called a cycle(Kreb's cycle or citric acid cycle)
Answer:
the 3ed one hope this helped
Explanation:
The answer is; D
The plasticity of rock in the mantle and the convection currents in the region are responsible for tectonic plate movements. The hot molten rock from deep in the mantle rise and is replaced by the cooler rock at the upper mantle. These convections are similar to those of water in a boiling pot. As the tectonic plates move (as they are dragged by these convections) and collide, earthquakes are caused. In addition, at subductions zones (where two plates collide) there occurs high volcanic activity.
The best answer is B (semi permeable)
The cell membrane of a red blood cell is semi permeable membrane. This is a type of biological membrane that will allow certain molecules or ions to pass through while barring others.
Red blood cells have very thin membranes that allow oxygen diffuse through quickly. They are also permeable to water and osmosis across the membrane occurs very rapidly. In the body, they are bathed in isotonic plasma in which case water movement into the cell is equal to water movement out of the cell and so the cells remain intact.
