Answer:
<em><u>Concentration gradients:</u></em>
- Passive transport: In favor ----> Simple Diffusion and facilitated diffusion
- Active transport: Against
<u><em>Phospholipid bilayer</em></u>
- Passive transport: Small particles or molecules can pass through the membrane----> Simple diffusion
- Active transport: Big particles or molecules need proteins to pass from one side to the other of the membrane
<u><em>Membrane proteins</em></u>
- Passive transport: Channel proteins in favor of electrochemical gradient---> Facilitated diffusion
- Active transport: Transporters or carrier proteins help molecules to pass to the other side of the membrane the electrochemical gradient.
Explanation:
<u>Diffusion:</u> Refers to the pass of some small polar hydrophilic molecules through the lipidic bilayer. There are momentary membrane openings that allow small molecules to freely move from one side to the other in favor of the electrochemical gradient. These openings are the result of the lipids movements. The membrane 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.
<u>Facilitated diffusion:</u> Occurs when big hydrophilic molecules cannot move freely across the membrane. In these situations, channel proteins are in charge of passive transport. Facilitated diffusion also occurs in favor of electrochemical gradients, meaning that molecules move from the more concentrated side to the less concentrated side.
<em>Simple diffusion and facilitated diffusion are passive transport processes because the cell does not need any energy to make it happen. </em>
<u>Active transport </u>is against the electrochemical gradient, so it does need energy to happen. Molecules move from a lower concentration side to a higher concentration side. This process is always in charge of carrier proteins. In primary active transport, the energy needed comes from the ATP molecule. In secondary active transport, the energy comes from the membrane electric potential.
<u>Transmembrane proteins</u> act in active and passive transport, connecting cells, and participating in signal transduction.
Channel proteins act by passive transport (these proteins do not need energy to carry in or out substances. They do it according to an electrochemical gradient) and carrier proteins act during active transport (these proteins do need the energy to transport substances because they do it against an electrochemical gradient). These transmembrane proteins carry in those substances needed by the cells to properly perform their activities, and they can also carry out waste substances.
A Euglena is green in color because it has chloroplasts which contains chlorophyll contributing to the green color of the organism. Euglena are organisms that are single-celled which are found in fresh water. The specialized body structure located at the base of the tail is called the flagella which are used by these organisms to move in water.
Answer:
the number of limbs they have
Explanation:
Because you can not change the way they breathe because it is natural
You can not change the structure of the cell because it is also natural
You cannot change their sensitivity of their smell because it is also natural
so the answer is Abecause that one is a physical change that can be passed from generation
Answer:
B modern society
Explanation:
If we still lived in the Dark Ages, we'd all be so busy farming and fighting for survival that there would be no space for leisure goods like contact lenses or developing technology like cell phones. Our modern society enables us to have job specialization: not everyone has to farm. Some people can take time to invent contact lenses. Some people can make those contact lenses.
Why not A: scientific discoveries didn't really impact rock concerts, unless you count the speaker systems. That's too loose.
Why not C: factories produce those items, but they don't directly influence their generation.
Why not D: political change has nothing to do with these items.
<span>The answer is cell wall. It is the rigid outer layer
of plant cells that is composed of subunits of cellulose molecules,
pectin, lignin, or hemicellulose. It enables
the plant to withstand turgor pressure,
without bursting, required to give them support.</span>