2.1.1 Basic components of life

Question 1

Function of Cell surface (plasma) membrane

Answer 1

• regulates movement of substances into and out of the cell
• has receptor molecules on it - allows it to respond to chemicals like hormones
•a phospholipid layer that covers a cell’s surface and acts as a barrier between the inside of a cell and the cell’s environment

Question 2

Function of Cytoplasm

Answer 2

• many cellular processes occur in the cytoplasm
• holds components in place
• protects organelles from damage

Question 3

Function of the Nucleus

Answer 3

• controls the cells activities (by controlling the transcription of DNA)
• DNA contains instructions to make proteins
• pores allows substances to move between the nucleus & move between the nucleus & the cytoplasm

Question 4

Function of the Nucleolus

Answer 4

• makes ribosomes
• dense spherical structure inside the nucleus where RNA is made

Question 5

Function of the Nuclear envelope

Answer 5

• keeps contents of nucleus separate from the cytoplasm of the cell
• has nuclear pores to allow mRNA and other chemicals to flow through
• made of phospholipid bilane
• double membrane that encloses the nucleus, perforated with pores that regulate traffic with the cytoplasm

Question 6

Function of the Mitochondria

Answer 6

• site of aerobic respiration, where ATP is produced
• found in large numbers in cells that are very active and require lots of energy
• outer and inner membrane, inner membrane folded into cristae

Question 7

Function of the Vesicles

Answer 7

• transports substances in + out of the cell & between organelles
• are formed by the golgi apparatus, the endoplasmic reticulum or the cell surface

Question 8

Function of the Lysosomes

Answer 8

• contains digestive enzymes kept separate from cytoplasm by the surrounding membrane
• can be used to digest invading cells
  or used to breakdown worn out components of the cell

Question 9

Function of the Smooth endoplasmic reticulum

Answer 9

• synthesises & processes lipids
• folded membrane-bound sacs with no ribosomes,

Question 10

Function of the Rough endoplasmic reticulum

Answer 10

• folds & processes proteins that was made at the ribosomes
• folded membrane-bound sacs studded with ribosomes involved in protein production

Question 11

Function of the Ribosomes

Answer 11

• site of protein synthesis

Question 12

Function of the Golgi apparatus

Answer 12

• processes & packages new lipids & proteins
• makes lysozymes
• system of membranes that modifies and packages proteins for export by the cell

Question 13

Function of the cell wall

Answer 13

• provides cell with support

Question 14

Function of the Large permanent vacuole

Answer 14

• maintain structure of the cell
• membrane called the tonoplast
• selectively permeable (some small molecules can pass through)

Question 15

Function of the Chloroplast

Answer 15

• site of photosynthesis
• some parts of photosynthesis occurs in the grana & other parts on the stroma

Question 16

Function of the Centrioles

Answer 16

• involved with the separation of chromosomes during cell division
• small tubes of protein fibres that produce the spindle fibres for cell division

Question 17

Function of the Cilia

Answer 17

• the microtubules allow the cilia to move
• movement is used by the cell to move substances along the cell surface
• hairlike projections that extend from the plasma membrane and are locomotive

Question 18

Function of the Flagella

Answer 18

• the microtubules contract to make the flagellum move
• flagella propels cells forward

Question 19

what is a prokaryote?

Answer 19

• unicellular organism that lacks a nucleus and membrane bound organelles

Question 20

what is a eukaryote?

Answer 20

• a cell that contains a nucleus and membrane bound organelles

Question 21

what is magnification?

Answer 21

makes specimen appear larger than it is, especially with a lens or microscope

Question 22

what is resolution?

Answer 22

ability to distinguish between two separate structures

Question 23

what is a transmission electron microscope?

Answer 23

a microscope that transmits a beam of electrons through a very thin slice of specimen and that can magnify up to 200,000 times

Question 24

what is a light microscope

Answer 24

microscope that uses a beam of light passing through one or more lenses to magnify an object up to x1,500

Question 25

what is a scanning electron microscope?

Answer 25

a microscope that uses electron beams to scan the surface of the sample up to x100,000 giving a 3D image

Question 26

what is sectioning?

Answer 26

process of slicing tissue embedded in wax or other substance into very
thin slics