Are muscles organs? (please give me a yes or no answer with an explanation, im confused ;v;)

2. What is an example of something studied on the molecular level (as opposed to the atomic level)?

Dmitriy789 [7]

Answer:

Something studied on the molecular level is the water.

Explanation:

Water is a molecule formed by two hydrogen atoms and one oxygen atom, whose chemical representation is H₂O. It is a molecule whose polarity makes it a universal solvent of other polar molecules.

The molecular level corresponds to the level of organization where two or more atoms unite to form molecules or substances, united by chemical bonds. H₂O is studied at this level due to its chemical structure.

With respect to other options:

Hydrogen and oxygen are atoms, and correspond to the level of atomic organization.
Protons are particles that are part of an atom, and correspond to the subatomic level.

6 0

2 years ago

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

Which type of transport takes place when a protein allows an ion to enter a

kolezko [41]

Answer: Im pretty sure its C

Explanation:

8 0

3 years ago

Read 2 more answers

Which factor would not increase the production of glucose by photosynthesis in plants? A) increased exposure to sunlight Elimina

mars1129 [50]

the correct answer is C

7 0

3 years ago

Read 2 more answers

Which is a mechanism for restricting the movement of proteins in the plasma membrane? Choose one or more:

alexgriva [62]

Answer:

The correct answers are option A. "tethering proteins to the cell cortex", B. "using barriers such as tight junctions", C. "tethering proteins to the extracellular matrix", D. "forming a covalent linkage with membrane lipids", E. "tethering proteins to the surface of another cell"

Explanation:

According to the fluid-mosaic model, the components of cell membranes are in constant movement forming a barrier to avoid unwanted exterior component internalization and to avoid the loss of precious internal components. This constant movement could cause that proteins move across the plasma membrane. But, this is avoided by several mechanisms including:

A. Tethering proteins to the cell cortex. The cell cortex is a rigid structure made of actin and actomyosin. Proteins found in the plasma membrane are tethered to this structure to restrict their movement.

B. Using barriers such as tight junctions. Tight junctions are barriers found in epithelia made of claudin and occludin proteins. These barriers are impenetrable, which avoid the movement of proteins in the cell membrane.

C. Tethering proteins to the extracellular matrix. The extracellular matrix is made of several proteins and macromolecules that provide a structural and biochemical support to cells that are nearby. Proteins could be tethered to this rigid structure as well.

D. Forming a covalent linkage with membrane lipids. The proteins in the cell membrane that form a covalent linkage with membrane lipids are known as lipid-anchored proteins, or lipid-linked proteins.

E. Tethering proteins to the surface of another cell. When cell-cell communication take place it is possible that proteins in the cell membrane got tethered to the surface of the other cell.

6 0

3 years ago