True or False? Buoyant forces act on objects that are only floating in air.

A) Compare and contrast diffusion, passive transport (diffusion & facilitated), primary active transport and secondary activ

zheka24 [161]

Answer:

Passive transport: It does not need any energy to occur. Happens in favor of an electrochemical gradient. Simple diffusion and facilitated diffusion are kinds of passive transport.

Simple diffusion: molecules freely moves through the membrane.

Facilitated diffusion: molecules are carried through the membrane by channel proteins or carrier proteins.

Active transport needs energy, which can be taken from the ATP molecule (Primary active transport) or from a membrane electrical potential (Secondary active transport).

Explanation:

Diffusion: This is a pathway for some small polar hydrophilic molecules that can freely move through the membrane. Membrane´s permeability depends on the size of the molecule, the bigger the molecule is, the less capacity to cross the membrane it has. Diffusion is a very slow process and to be efficient requires short distances and pronounced concentration gradients. An example of diffusion is osmosis where water is the transported molecule.

Facilitated diffusion: Refers to the transport of hydrophilic molecules that are not able to freely cross the membrane. Channel protein and many carrier proteins are in charge of this passive transport. If uncharged molecules need to be carried this process depends on concentration gradients and molecules are transported from a higher concentration side to a lower concentration side. If ions need to be transported this process depends on an electrochemical gradient. The glucose is an example of a hydrophilic protein that gets into the cell by facilitated diffusion.

Simple diffusion and facilitated diffusion are passive transport processes because the cell does not need any energy to make it happen.

Active transport occurs against the electrochemical gradient, so it does need energy to happen. Molecules go from a high concentration side to a lower concentration side. This process is always in charge of carrier proteins. In primary active transport the energy needed comes from the ATP molecule. An example of primary active transport is the Na-K bomb. In secondary active transport, the energy comes from the membrane electric potential. Examples of secondary active transport are the carriage of Na, K, Mg metallic ions.

7 0

3 years ago

In his study of the Mediterranean fruit flies (Ceratitis capitata), Matthew Gage (1991) found evidence of sperm competition by o

Murrr4er [49]

Answer:

<h2>Males produces less amount of sperms when mated alone.</h2>

Explanation:

Mediterranean fruit flies are also called as medfly. They are a type of pests that are yellow and brown in color and are originated from Sub- Sahara Africa and also found in California, Texas and some other places.

When Matthew Gage analyzed then, he found the males that mate alone produce fewer sperms while those mates in the presence of other males produce more sperms.

8 0

3 years ago

What isPlasma membrane

Shalnov [3]

answer:

plasma membrane a microscopic membrane of lipids and proteins which forms the external boundary of the cytoplasm of a cell or in closes a vacuole, and regulates the passage of molecules in and out of the cytoplasm

answer number 2

the plasma membrane or cell membrane, is the phospholipid layer that surrounds the cell and protects it from outside environment.

you can use either answer if you have to type or write an answer

3 0

3 years ago

A human’s knee joint is best described as

vesna_86 [32]

Answer:

A synovial joint

Explanation:

because it is highly moveable, allows for flexibility, has ligaments for stability, and has cartilage for protection of the articulating bones. ... It is a synarthrosis joint because it cannot move.

4 0

2 years ago

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What is the formula for Glucose

Rom4ik [11]

Answer: Glucose also called dextrose one of a group of carbohydrates know as simple sugars.

4 0

3 years ago

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