There are 2 types of transport mechanisms that involve the movement of materials across the cellular membrane:
1. Passive Transport Mechanisms which is the movement of materials that does not require energy. Instead the movement relies on the permeability of the cell. Under this are three kinds of passive transport mechanisms:
a. Simple Diffusion:
- the movement of materials from a region of higher concentration to lower concentration. No external energy is necessary for the movement. The materials supply the energy themselves.
b. Facilitated Diffusion:
- This differs from simple diffusion because the movement is facilitated by proteins that make up the structure of the membrane. The proteins include channel proteins that allow ions and smaller molecules to cross the membrane. The other protein are the carrier proteins, which bind to materials like sugar molecules and move it across the membrane.
c. Osmosis:
- This is the diffusion of water across the membrane. Osmosis moves water from regions where there are more water molecules of water per volume to regions where there are less water molecules per volume.
2. Active transport on the other hand is a movement mechanism that requires energy. It uses the energy to send materials against the direction it is coming from through simple diffusion. This mechanism is used in a way to keep unwanted ions or other materials out of the cell.
Answer:
Channels discriminate between solutes mainly on the basis of size and electric charge.
Explanation:
Cant see the following animals
Answer:
8.800s
Explanation:
When the performer swings, she oscillates in SHM about Lo of the string with time period To = 8.90s.
First, determine the original length Lo, where for a SHM the time period is related to length and the gravitational acceleration by the equation
T = 2π×√(Lo/g)..... (1)
Let's make Lo the subject of the formulae
Lo = gTo^2/4π^2 ..... (2)
Let's put our values into equation (2) to get Lo
Lo = gTo^2/4π^2
= (9.8m/s^2)(8.90s)^2
------------------------------
4π^2
= 19.663m
Second instant, when she rise by 44.0cm, so the length Lo will be reduced by 44.0cm and the final length will be
L = Lo - (0.44m)
= 19.663m - 0.44m
= 19.223m
Now let use the value of L into equation (1) to get the period T after raising
T = 2π×√(L/g)
= 2π×√(19.223m/9.8m/s^2)
= 8.800s