Cell Transport

pinocytosis

"cell drinking" the process of taking up liquid from the surrounding environment (extracellular fluid). Tiny pockets form along the membrane, fill with liquid, and pinch off.

Phagocytosis

"cell eating" extensions off the cell membrane surround a particle and package it within a vesicle and then the cell engulfs it. Ex: amoebas, macrophages use this process.

cell membrane

a boundary that encloses the cell and separates it from the external environment. It regulates what enters and leaves the cell.

Equilibrium

a condition in which the concentration of a substance is equal throughout a space.

What do vesicles contain

a phospholipid bilayer

Each phospholipid is made up of....

a polar and hydrophilic phosphate head two non polar and hydrophobic fatty acid tails

Diffusion

a specific type of passive transport the movement of particles from an area of high concentration to an area of low concentration. Dissolved particles that are small and non polar such as CO2 and O2 can diffuse directly throughout the cell membrane.

Membrane Potential

an electrical charge that exists across the cell membrane

Channel Pumps

certain channel proteins in the cell membrane push molecules against there concentration gradient to maintain unequal levels using ATP. These channel proteins are very specific. Can work into and out of the cell.

Why are proteins embedded in the cell membrane?

to help with transport

Why do cell transport substances across the cell membrane?

to maintain homeostasis

why is it called the phospholipid bilayer?

two layers of phospholipids

ATP Hydrolysis

when the bond between the last two phosphates is broken, a large amount of energy stored is released. ATP= charged form ADP=uncharged form

What organelle in the cell makes proteins?

The organelles in the cell that makes proteins are ribosomes.

If that protein's job is outside of the cell, where must it go to be packaged and distributed?

If the proteins job is outside of the cell, the protein must be packaged and distributed by the golgi apparatus.

Sodium Potassium Pump

-Located on the cell membrane of all animal cells. -responsible for 1/5 of cell's total ATP usage. -Pumps sodium (Na) out of cells and potassium(K) into cells-- both against there concentration gradient. -in order to maintain cell membrane potential intracellular concentrations of sodium must be low and potassium must be high. (REFER TO VIDEO)

ADP+P=

ATP

What is the difference between the two?

Active transport requires energy and passive transport does not.

What type of transport requires moving substances from low concentration to high concentration (against their concentration gradient)?

Active transport requires moving substances from low to high concentration, or against there gradient.

What does ATP stand for?

Adenosine Triphosphate.

Describe the events of an isotonic solution.

An isotonic solution occurs when there is an equal amount of solute on the inside and outside of the cell, so water moves both in and out, because there is already an equilibrium. An isotonic solution is a solution that causes water to move inside and outside of the cell at the same time, and isotonic solution=same concentration. All cells strive to have a isotonic solution.

What is another name for a membrane-bound sac?

Another name for a membrane bound sac is vesicle.

What organelle is responsible for keeping the plant cells nice and plump?

Central Vacuole

If molecules are too large to diffuse through the cell membrane, what must they pass through? Describe. Whats another name?

If molecules are too large to diffuse through the cell membrane, they must pass through ion channels. Ion channels are transmembrane proteins embedded in the cell membrane that offer an opening for slightly larger molecules across the cell membrane. They are also called facilitatated diffusion, because molecules move from high to low concentration in a process facilitated, or enabled, by transport proteins. Examples of ions: Potassium(K+) Sodium(Na+) Calcium(Ca+) and Chloride(Cl-). The definition of Ion channels is: when they are open, charged ions can pass through the cell membrane, entering or leaving the cell.

What would you call the process if the cell was taking in a liquid?

If the cell was taking in a liquid, you would call the process pinocytosis.

What is movement across the cell membrane used to maintain?

Movement across the cell membrane is used to maintain homeostasis.

Describe the events of a hypertonic solution thoroughly.

If there is more solute on the outside of the cell, than on the inside of the cell, water moves outside of the cell. This is because water moves from a high to low concentration gradient. This causes the cell to shrink, because it is losing water. Water wants to move toward the solute because solute is what is being dissolved. This is called a hypertonic solution(highly concentrated with solute)

If water move in and out of a cell at the same rate, what will happen to the cell?

If water moves in and out of the cell at the same rate, then the cell size will remain the same.

If water moves into a cell, what will happen to the cell?

If water moves into a cell, the cells will swell and ultimately burst.

If water moves out of a cell, what will happen to the cell?

If water moves out of a cell, then the cell will shrink.

Describe the events of a hypotonic solution thoroughly.

In a hypotonic solution, the water from the outside of the cell moves into the cell. This happens because there is more solute inside the cell, and the water from the outside moves in, because it moves from a high to low concentration gradient.

Ion channels

Ion channels are transmembrane proteins embedded in the cell membrane that offer an opening for slightly larger molecules across the cell membrane. Also called facilitated diffusion because molecules move from high to low concentration in a process facilitated by transport proteins. When they are open charged ions ccan pass through the cell membrane entering or leaving the cell.

When a substance does not require energy to move, what causes its movement?

Its move is caused by a concentration gradient. The substance moves from a high to low concentration, in order to reach equilibrium(the condition in which a substance is equal.)

Vesicles

Membrane bound sacs that can bring substances in and out of the cell membrane

What is osmosis?

Osmosis is a specific type of cell transport, and it is the movement of water across a semi-permeable membrane.

These are passageways pass through _________________ that are embedded in the cell membrane.

PROTEINS

Examples of ions that pass through ion channels

Potassium K+, Sodium Na+, Calcium Ca+, Chloride Cl-

What are embedded within the cell membrane?

Proteins

Example of Channel Pumps

Sodium- Potassium Pump

What is energy called in our bodies?

The energy in our body is called ATP.

What process involves the cell membrane pinching in around a substance to form a sac within the cell?

The process is called endocytosis.

By what process does the protein exit the cell?

The protein exits the cell by exocytosis.

What is the protein packaged in?

The protein is packaged in vesicles.

What type of solution will cause the cell staying the same size to happen?

The type of solution that causes this to happen is an isotonic solution. In isotonic solution is when there is no net mocement of the water because equilibrium is already reached. An isotonic solution can be defined as a solution that causes water to move and out of the cell at the same time. Isotonic=same concentration.

What type of solution will cause cell shrinking to happen? Describe

The type of solution that will cause this to happen is a hypertonic solution. If the environment surrounding the cell has a greater amount of solute than the cell itself, than the water inside the cell will move out of the cell. This is because water moves from a high to low concentration. Hypertonic solution means highly concentrate with solute.

What type of solution will cause cell swelling to happen?

The type of solution that will cause this to happen is a hypotonic solution. If there is more solute inside the cell than outside the cell, the water from outside the cell will move towards the solute to create an equilibrium. The term hypotonic solution means lowly concentrated with solute.

What are the two main types of cellular transport?

Two main types of cellular transportation are active and passive transport.

When the solute concentrations inside and outside of the cell are the same

dynamic equilibrium

Substances tend to move from an area of ___________ concentration to an area of __________ concentration. This process is called __________________________ and it strives to reach ______________________________, which is the condition when the concentration of a substance is equal throughout a space.

high;low;diffusion; equilibrium

when there is more solvent outside the cell solvent particle move

inside

when the cell volume is smaller, the concentration on the outside of solute is

larger

the more solute outside the cell membrane

the smaller it becomes

Because the phosphate heads are so tightly packed together...

only extremely small and non polar molecules can pass directly through the cell membrane

when there is more solvent inside the cell solvent particle move

outside

Specific reasons for cell transport to maintain homeostasis

pH Temperature Ions(to correct ion levels) Hydration

What is another name from the cell membrane

phospholipid bilayer

When the cell volume is larger, the solute concentration on the outside is

smaller

Vesicle Movement

substances that are too big for protein channels can enter and exit in vesicles.

If the inside of a cell is negatively charged and the outside is positively charged, in which direction will each charge passively move?

the charge outside the cell will move inside

The less solute that is outside the cell membrne

the larger the cell becomes

Endocytosis

the movement of substances into a cell by means of a vesicle

Exocytosis

the movement of substances out of a cell by means of a vesicle. this process is used by the golgi apparatus to export proteins.

The type of cell transport is used depending on..

the particular type of molecule that needs to be moved in and out of the cell