JEOPARDYCELL MEMBRANE

CHAPTER 5JORDYN GARDNER

Membrane

structure and

function

Membrane

Proteins

Diffusion Osmosis Exocytosis and

endocytosis

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Lipid bilayer

What is the Structural basis of cell membranes?

Fluid Mosaic Model

By this model, a cell membrane has a mixed composition of phospholipids, glycolipids, sterols, and

proteins. What is it?

2, lipids, and phospholipids

A cell membrane includes ___ layers composed mainly of ________& _________.

True

True or False: Many different proteins having different functions are embedded in the membrane or

positioned at its surfaces?

A phosphate-containing head and two fatty acid tails attached to a

glycerol backbone.

What makes up a phospholipid ?

-Serves as a boundary between the outside environment and the inside of the cell

-gives form and shape to cells- Can connect on cell to two or more adjacent

cells- -helps vesicles form

- (other answers may be acceptable)

What does the cell membrane do?

Adhesion proteins

What helps cells of the same type locate, stick together, and remain in the same proper tissues?

Communication Proteins

These from channels that match up across the plasma membranes of two cells; they let signals and substances

flow rapidly between their cytoplasm

Receptor Proteins

These bind extracellular substances, such a s hormones, that trigger changes in cell activities

Recognition Proteins

Like molecular fingerprints, they identify each cell as belonging to a particular tissue or individual.

Transport Proteins

These passively let solutes cross the membrane through their interior or they actively pump them

through.

Diffusion

The name for the net movement of like molecules or ions down a concentration gradient.

It has selective permeability

What does it mean when its molecular structure lets some substances but no others cross it in certain ways,

at certain times?

Down

Does diffusion go up or down a concentration gradient?

Yes

Is a concentration gradient a form of energy?

The gradient’s steepness, molecular size, temperature, and electric or pressure gradients that may be

present.

What factors influence the rates of movement down a concentration gradient?

Osmosis

When water molecules diffuse down the water concentration gradient and thus cross that membrane

what occurs?

hypotonic

Which tonicity is the one with fewer solutes?

hypertonic

What tonicity has more solutes?

Isotonic

This solution has the same amount of solutes.

Osmotic pressure

The amount of force preventing further increase in a solution’s volume?

Exocytosis

What is it called when a vesicle moves to the cell surface, and the protein-studded lipid bilayer of its

membrane fuses with the plasma membrane?

endocytosis

When a cell takes in substances near its surface it is?

Cell eating

Phagocytosis is another word for..?

yes

Do Exocytosis, and endocytosis continually replace and withdraw patches of its plasma membrane?

Move large packets of materials across a plasma

membrane.

Overall what does Exocytosis and endocytosis do?