Bio 111 Chapter 3 "cells"

Front 1

list four primary types of membrane proteins, and explain their function

Back 1

1) Receptor proteins: bind to chemicals in the cell's external environment and, by doing so, regulate certain processes within the cell.
2) Recognition proteins: give each cell a "fingerprint" that makes it possible for the bod'y immune system to distinguish the cells that belong inside you from those that are invaders and need to be attacked.
3) Transport proteins: transmembrane proteins that help large and/or strongly charged molecules to pass through the plasma membrane. wide variety of shapes and sizes allow wide variety of molecules to be transported.
4)Enzymatic proteins: accelerate chemical reactions on the cell membrane's surface

Front 2

define cholesterol

Back 2

a lipid that helps the membrane maintain its flexibility.

Front 3

define plasma membrane

Back 3

fluid mosaic of proteins, lipids, and carbohydrates

Front 4

define diffusion

Back 4

a form of passive transport that results in an even distribution of molecules

Front 5

define osmosis

Back 5

the diffusion of water across a membrane. As molecules diffuse across a plasma membrane, molecules of water also move across the membrane, equalizing the concentration of water inside and outside of the cell.

Front 6

define solute

Back 6

particle being dissolved

Front 7

define solvent

Back 7

gas or liquid doing the dissolving

Front 8

define facilitated diffusion

Back 8

when spontaneous diffusion across a plasma membrane requires a transport protein

Front 9

define passive transport

Back 9

molecular movement occurs spontaneously, without the input of energy. e.g. diffusion and osmosis

Front 10

define hypertonic solution

Back 10

has a greater concentration of solutes than the solution inside the cell. As a consequence, if the cell membrane is not permeable to the solutes, water will move out of the cell into the surrounding solution, equalizing the solute concentration inside and out (and the cell shrivels).

Front 11

define hypotonic solution

Back 11

has lower solute concentration than the solution inside the cell. If the cell membrane is not permeable to the solutes, water will move into the cell and it will swell.

Front 12

define isotonic solution

Back 12

the concentration of solutes is the same inside and outside of the cell.

Front 13

define tonicity

Back 13

the concentration of solutes outside the cell relative to inside the cell

Front 14

define active transport

Back 14

proteins embedded within the membrane act like motorized revolving doors, pushing molecules into the cell regardless of the concentration of those molecules on either side of the membrane.

Front 15

define primary active transport

Back 15

When active transport uses energy directly from ATP to fuel the revolving door

Front 16

define secondary active transport

Back 16

the transport protein simultaneously moves one molecule against its concentration gradient while letting another flow down its concentration gradient. NO ATP IS USED directly.

Front 17

define endocytosis and list the 3 types

Back 17

the basic process of the plasma membrane oozing around an object that is outside of the cell, surrounding it, forming a little pocket
1)Phagocytosis:the process by which relatively large particles are engulfed by cells
2) Pinocytosis: the process of cells taking in dissolved particles and liquid
3) Receptor-mediated endocytosis: really specific

Front 18

define exocytosis

Back 18

process for getting molecules out of the cell

Front 19

define vesicle

Back 19

The "little pocket" created by endocytosis

Front 20

List the 3 primary connections between animal cells

Back 20

1) Tight junctions: form continuous, water-tight seals around cells and also anchor cells in place.
2) Desmosomes: are like spot welds or rivets that fasten cells together into strong sheets.
3) Gap Junctions: pores surrounded by special proteins that form open channels between two cells

Front 21

define contact inhibition

Back 21

Normal cells generally stop dividing when they bump up against other cells

Front 22

define plasmodesmata

Back 22

connect plant cells, and enable them to communication and transport between them.