Biology Unit 3 Chapter 2

Front 1

Apoptosis

Back 1

Programed cell death

Front 2

Plasma Membrane

Back 2

Controls entry into and out of the cell. The plasma membrane comprises a phospholipid bilayer into which proteins and glycoproteins protrude.

Front 3

Antigens

Back 3

Labels or identifys one cell belonging to a particular organism. Made up of proteins and carbohydrates.

Front 4

Diffusion

Back 4

the net movement of substances, typically in a solution, from a region of high concentration of the substance to a region of low concentration. The process of diffusion does not require energy.

Front 5

Channel mediation

Back 5

some substances that are unable to carry out simple diffusion across the phospholipids bi-layer, are instead transported through protein channels. Substances move from high concentration to low concentration without the use of energy.

Front 6

Carrier mediation

Back 6

sometimes even the help of channels is not enough an a carrier molecule is required to move molecules through the concentration gradient. Also known as facilitated diffusion.

Front 7

Active Transport

Back 7

the net movement of substances into or out of the cell against the concentration gradient. This is an energy requiring process.

Front 8

Endocytosis

Back 8

The bulk transport of solid particles into a cell. The material is engulfed into a lysosome and broken down into the cell.

Front 9

Exocytosis

Back 9

The bulk transport of solid particles out of a cell. The particles are packaged and the vesicle that holds them is then fused to the plasma membrane and transported out of the cell.

Front 10

The Nucleus

Back 10

The control centre of the cell. It holds all the genetic material incuding DNA in the form of chromosomes and RNA.

Front 11

Mitochondrion

Back 11

The site of cellular respiration and the production of ATP. Has a distinct layered inner membrane.

Front 12

Ribosomes

Back 12

The organelle where protein production occurs. Can either be free ribosomes or attatched to the Endoplasmic Reticulum. Made up of proteins and rRNA.

Front 13

Endoplasmic Reticulum

Back 13

Responsible for the transport of substances within a cell. Membranes form the channel walls. Can be Smooth ER or Rough ER depending on whether ribosomes are present.

Front 14

Golgi Apparatus

Back 14

Role is to shift proteins out of the cell. Packages substances into vesicles so they can be shifted out of the cell using exocytosis.

Front 15

Lysosomes

Back 15

Sac-like structures surrounded by a membrane, and filled with fluid containing dissolved digestive enzymes. They use their enzymes to destroy unwanted cell parts or damaged molecules from within or outside the cell.

Front 16

Cell Wall

Back 16

Semi rigid, protective structure deposited by the cell outside the cell membrane.

Front 17

Chloroplasts

Back 17

The production point of converting sun energy into chemical energy also know as photosynthesis.

Front 18

The Cell Skeleton

Back 18

An internal framework made up of microtubule, microfilament and intermediate filament, that provides strength and support for the cell.

Front 19

Microtubules

Back 19

They are hollow and are made of subunits of the protein tubulin.

Front 20

Microfilament

Back 20

They are solid, thinner and more flexible than microtubules. They are made of acitin.

Front 21

Intermediate filament

Back 21

They are made of a variety of proteins, depending on the cell and are very tough.

Front 22

Plasmodesmata

Back 22

The junction that exists in plant cells that allows communication between adjacent cells in spite of the thick wall.

Front 23

Occluding junctions

Back 23

This involves cell membranes coming together in contact with each other. This does not involve movement of material between cells.

Front 24

Communicating Junctions

Back 24

Also called gap junctions. They permit the passage of salt ions, sugars, amino acids and other small molecules as well as electrical signals from one cell to the other.

Front 25

Anchoring Junctions

Back 25

The most common type of junction between epithelial cells in areas such as the skin or uterus. They are also called desmosomes. This structure has a great tensile strength and acts throughout a group of cells, because of the connection from one cell to another.