Biology Unit Ii Exam

Front 1

Diffusion

Back 1

The net (or overall) movement of molecules or ions down a concentration gradient.

An essential way in which substances move into, through and out of cells.

Front 2

Passive Transport
(Facilitated Diffusion)

Back 2

A concentration gradient drives the diffusion of a solute across a cell membrane, with the assistance of a transport protein. The protein does not require energy to assist the solute's movement; thus, passive transport is also called facilitated diffusion

Front 3

Active Transport

Back 3

A transport protein uses energy to pump a solute against its gradient across a cell membrane. Energy, often in the form the form of a phosphate-group transfer from ATP, changes the shape of the transporter. The change causes the transporter to release the solute to the other side of the membrane

Front 4

Exocytosis

Back 4

A vesicle moves to the cell surface, and the protein-studded lipid bilayer of its membrane fuses with the plasma membrane. As the exocytic vesicle loses its identity, its contents are released to the surroundings.

Front 5

Endocytosis

Back 5

There are three pathways, but they all take up substances near the cell's surface. A small patch of plasma membrane balloons inward, and then it pinches off after sinking farther into the cytoplasm. The membrane patch becomes the outer boundary of an endocytic vesicle, which delivers its contents to an organelle or stores them in a cytoplasmic region.

Front 6

Phagocytosis

Back 6

"cell eating"

An endocytic pathway. Amoebas engulf microorganisms, cellular debris, or other particles. In animals, macrophages and other phagocytic white blood cells engulf and digest pathogenic viruses and bacteria, cancerous body cells and other threats

Front 7

Osmosis

Back 7

Water molecules diffuse in response to their own concentration gradient.

Front 8

Hypotonic

Back 8

When solute concnetrations differ, the fluid with the lower concentration of solutes

Front 9

Hypertonic

Back 9

Fluid with the higher concentration

Front 10

Isotonic

Back 10

Fluids that have the same solute concentration

Front 11

Crenation

Back 11

Contraction of a cell after exposure to a hypertonic solution, due to the loss of water through osmosis.

Front 12

Turgor Pressure
(Hydrostatic Pressure)

Back 12

Counter osmosis. The pressure that a volume of fluid exerts against a cell wall, membrane, tube or any other structure that holds it.

Front 13

Hemolysis

Back 13

The breaking open of erythrocytes (red blood cells) and the release of their contents (hemoglobin) into surrounding fluid (e.g., blood plasma). Hemolysis may occur in vivo or in vitro (inside or outside the body).

Front 14

Plasmolysis

Back 14

Process in animal cells where the plasma membrane engulfs the object cell wall due to the loss of water through osmosis.

Front 15

Pinocytosis

Back 15

"cell-drinking"

a form of endocytosis in which small particles are brought into the cell suspended within small vesicles which subsequently fuse with lysosomes to hydrolyze, or to break down, the particles. This process requires a lot energy in the form of adenosine triphosphate, the chemical compound used as energy in the majority of cells.

Front 16

Given concentrations, predict the direction of movement of water molecules across a selectively permeable membrane

Back 16

Tonicity dictates the direction of water movement across membranes: Water diffuses from a hypotonic solution to a hypertonic solution

Front 17

Hyoptonic

Back 17

Solution with the lower concentration

Front 18

Hypertonic

Back 18

Solution with the higher concentration

Front 19

Isotonic

Back 19

Solutions that have the same concentrations

Front 20

Predict whether cells will swell of shrink under various osmotic conditions

Back 20

If the fluid outside the cell is hypertonic water will follow its gradient and cross the membrane to the hypertonic side and the volume of the cell will decrease as water diffuses out of it. If the outside fluid is very hypotonic, the volume of the cell will increase as water diffuses into it.

Front 21

Energy

Back 21

The capacity to do work, it can be converted from one form to another, but it cannot be created or destroyed

Front 22

First Law of Thermodynamics

Back 22

Energy does not appear from nowhere and it does not vanish into anything

Front 23

Second Law Of Thermodynamics

Back 23

Entropy increases spontaneously

Front 24

Entropy

Back 24

Measure of how much the energy of a particular system has been dispersed. When we say that energy disperses, we mean that a system tends to change toward a state of maximum entropy.

Front 25

Reaction

Back 25

The chemical change process by which chemical bonds break, form or which.

Front 26

Reactamts

Back 26

Molecels that entera reaction

Front 27

Products

Back 27

Molecules that remain at the reaction's end