Cell Structure

Question 1

Cell Membrane

Answer 1

The outer covering of the cell composed of phospholipid. The cell membrane is semi-permiable and controls the entry and exit of materials/ molecules

Question 2

What is Phospholipid?

Answer 2

a lipid molecule containing phosphorus

Question 3

Cytoplasm

Answer 3

the fluid within the cell which contains the organelles. Provides support to the cell and contains ions such as glucose and protein

Question 4

Nucleus

Answer 4

the control centre of the cell. contains DNA in the form of chromosomes.

Question 5

Nucleolus

Answer 5

forms part of the nucleus and contains RNA. Is also responsible form the manufacture of ribosomes.

Question 6

Organelles

Answer 6

smaller structures located within the cytoplasm of the cell

Question 7

Centrosome

Answer 7

Rod like structures involved in cell replication and comprise two centrioles

Question 8

Centriole

Answer 8

found in the cytoplasm, migrates to opposite poles of the cell during cell replication, laying down microtubules to form the spindle as they go

Question 9

Mitochondria

Answer 9

responsible for cell respiration and where energy is extracted from food substances and stored in the cell - ATP production takes place here

Question 10

Ribosomes

Answer 10

responsible for protein synthesis and are often attached to the rough endoplasmic reticulum or floating free in the cytoplasm

Question 11

Rough endoplasmic reticulum

Answer 11

synthesis and transport of proteins in conjunction with the attached ribosomes

Question 12

Smooth endoplasmic reticulum

Answer 12

synthesis and transport of lipids and steroids

Question 13

Golgi apparatus

Answer 13

consists of flattened membrane sacs. involved in the production of lysosomes, secretory granules and plasma membrane. responsible for the transport and modification of substances such as glycoproteins

Question 14

Lysosome

Answer 14

collection of digestive enzymes in membrane sacs. they function by performing phagocytosis. forms part of the defence mechanism of the cell they destroy warn out organelles within the cell and in some cases the cell itself

Question 15

Cilia/ flagella

Answer 15

found on the outer surface of cell moves fluid and debris over the cell surface

Question 16

Diffusion

Answer 16

Occurs when molecules such as lipids use the process of diffusion to cross the membrane - Oxygen and water enter this way

Question 17

Facilitated diffusion

Answer 17

A form of passive diffusion where the substances enlist a carrier protein to cross the membrane - glucose uses this method to enter the cell

Question 18

Active transport mechanisms

Answer 18

Substances move from a region of low concentration to a high concentration gradient which requires a lot of energy as this process is hard work - molecules of adenosine triphosphate (ATP) sodium enter the cell this way