Cell transport/ Biology grade 9

white blood cells

engulf bacteria or other foreign invaders by phagocytosis as part of immune system defense against infection

What transport method do you think the Golgi apparatus uses to ship packages of proteins out of the cell?

Active transport

bilayer gives the cell membrane

a tough flexible structure that forms a strong barrier between the cell and its surroundings

Passive Transport

always happens when molecules that are in a high concentration area (crowded area) move to a lower concentration area (less crowded area). Requires no energy.

phospholipid lipid bilayer

cell membranes are made of a doubled layered sheet

Isotonic

fluids that of the same concentration. Body fluids are the same concentration as cell fluids.

Hypotonic

high water concentration, little sugars & salts compared to the cells. In this setting the cells would fill up with too much water and burst.

In hypertonic solution

higher solute concentration than the cell. Water molecules move out of cells.

active transport

i movement of molecules from a low concentration area (less crowded) into a high concentration area (more crowded) movement against the concentration gradient.

Where in the cell are Protein Pumps located?

in the cell membrane

Endocytosis equals

into the cell

The job of the cell membrane

is to regulate what enters and exits the cell.

What are the 3 molecules of the cell membrane primarily made of?

lipids, proteins, and carbohydrates(sugars)

Hypertonic

low water concentration, and lots of sugars & salts. In this setting the water would leave your cells and your cells would shrivel up and die!

In hypotonic solution

lower solute concentration than cell. Water molecules move into the cells.

What is the role of each molecule in the cell membrane?

1. Lipids- function as main part or structure of the cell membrane 2. Proteins- form channels or pumps to help move material across membrane 3. Carbohydrates- act as signals on cell membrane that allow cells to identify each other

exocytosis

Process by which cell will release large quantities molecules from the cell. A vesicle inside the cell carries a particle to the cell membrane and the vesicle sticks to the membrane and becomes a part of it so that the particle is forced out of the cell.

Why is the cell membrane said to be "selectively permeable"?

Since it allows certain things to go in and keeps other things out of the cell.

selectively permeable

Since some "stuff" can come in and some "stuff" must stay out, the cell membrane is said to be .

Why is it so important for your body to maintain water or sugar homeostasis?

To maintain equilibrium between the cell and it's environment.

Phagocytosis

cells use endocytosis to pull in solid particles .

In isotonic solution

concentration of solutes is the same inside and outside of cell, so water molecules move equally in both directions

Homeostasis

living things keep water, sugar, salts, etc. at a constant level

What direction are molecules being moved in active transport

opposite direction of diffusion or against the concentration gradient.

cell membrane

regulates what enters and leaves the cell and also provides protection and support.

Passive Transport is like

riding a bike downhill (from high to low) it does not require energy

Active Transport is like

riding a bike uphill (from low to high) it requires energy

Equilibrium

same amounts of substances are going in as coming out of cell

What types of molecules can diffuse through the cell membrane, without using a channel protein?

small molecules and molecules without charge

Endocytosis

the ability to wrap the cell membrane around a particle in order to pull it into the cell. This is use when molecules too big to fir thru protein channels or pass thru cell membrane.

all methods of active transport(protein pumps, endocytosis, exocytosis)

use energy (ATP)!! Protein pumps move smaller molecules through the cell membrane. Endocytosis and Exocytosis, use the cell membrane to engulf substances then move them in or out of the cell.

Blood glucose or carbohydrates

use facilitated diffusion to move through channel proteins

Body fluids

use osmosis to move in out of cells, from higher concentrations to lower concentration

oxygen

uses diffusion to enter blood cells

Diffusion

when any molecule moves from high to low concentration.

facilitated diffusion

when large or charged molecules move through a channel protein in the cell membrane. the molecule must be the right size for the channel protein in order pass without energy

Osmosis

when water moves from high to low concentration

Pinocytosis

cells use endocytosis to pull in liquid particles

Active transport requires

energy in form of ATP and uses protein pumps

exocytosis equals

exiting the cell

moving down a concentration gradient means

Molecules will always move to areas where it is less crowded for them, without any energy needed or movement from a high concentration area to a low concentration area

3 types of passive transport

Diffusion, Osmosis and Facilitated Diffusion. Remember that all 3 require no energy

Why is facilitated diffusion a form of passive transport? What types of molecules need this type of help getting into the cell?

Facilitated Diffusion is considered passive transport because it allows things to move into the cell through protein channels and requires no energy to do this. It allows larger molecules and molecules with charge to pass through.