2.1 cell structure

Question 1

describe the roles if the cytoskeleton

Answer 1

• moves cilia and flagella
• provides support for the cell
• changes the shape of the cell

Question 2

what is the nucleus?

Answer 2

• the part of the cell that contains the genetic information
• it is surrounded by a double membrane called the nuclear envelope

Question 3

what is the function of the smooth endoplasmic reticulum?

Answer 3

• responsibe for lipid and carbohydrate synthesis

Question 4

what is the function of the rough endoplasmic reticulum?

Answer 4

• contains ribosomes for protein synthesis
• helps to transport molecules from one area of the cell to another.

Question 5

What is the nucleolus?

Answer 5

the inner part of the nucleus that is responsible for making ribosomes.

Question 6

What are lysosomes?

Answer 6

specialised vesicles that contain hydrolitic enzymes for breaking down cell organelles

Question 7

what are cilia and flagella?

Answer 7

• part of the cytoskeleton, they help with cell movement.

Question 8

what is the cytoskeleton made from?

Answer 8

• micro filaments
• micro tubules
• intermediate fibres

Question 9

what is the cell wall?

Answer 9

• a freely permeable defense mechanism for pathogens.

Question 10

what is the function of the golgi apparatus?

Answer 10

• modifies and packages proteins
• produces lysosomes

Question 11

what is the vacuole?

Answer 11

a fluid filled sack found in plant cells, it helps to maintain their turgor

Question 12

what are ribosomes?

Answer 12

the site of protein synthesis

Question 13

what are mitochondria?

Answer 13

the site of aerobic respiration

Question 14

what is the structure of mitochondria?

Answer 14

a membrane that forms cristae, with an inner fluid matrix

Question 15

what are chloroplasts?

Answer 15

the site of photosynthesis

Question 16

what is the structure of chloroplasts?

Answer 16

a double membrane with a fluid called stroma

Question 17

how does a transmission electron microscope work?

Answer 17

electromagnets are used to focus a beam of electrons through the specimen

Question 18

what is the resolution of a TEM?

Answer 18

0.05-2nm

Question 19

what is the magnification of a TEM?

Answer 19

X 1 000 000

Question 20

How does a scanning electron microscope work?

Answer 20

a beam of electrons is scanned across the specimen which knocks electrons off of the specimens. They the gather in a cathode ray tube to form an image.

Question 21

what is the resolution of a SEM?

Answer 21

5-50nm

Question 22

What is the magnification of a SEM?

Answer 22

X 500 000

Question 23

what are some advantages of electron microscopes?

Answer 23

• higher resolution and magnification than light microscopes
• SEM produces a 3D image
• produces detailed images

Question 24

what are some disadvantages of electron microscopes?

Answer 24

• very expensive
• must be trained to use
• black and white image
• complex staining required
• image may contain artefacts
• specimen must be dead and in a vacuum

Question 25

what is an eyepiece graticule?

Answer 25

a measuring device found within the eyepiece of a microscope

Question 26

what is a stage micrometer?

Answer 26

a precise measuring device used alongside the eyepiece graticule to calibrate a microscope

Question 27

what is resolution?

Answer 27

the ability to distinguish clearly between two spearate points

Question 28

what are photomicrographs?

Answer 28

the image produced by a light microscope

Question 29

what are electron micrographs?

Answer 29

the image production by an electron microscope

Question 30

what is magnification?

Answer 30

the number of times large an image appears

Question 31

what is the magnification calculation?

Answer 31

image size = actual size X magnification

Question 32

what is the resolution of a light microscope?

Answer 32

200nm

Question 33

what is the magnification of a light microscope?

Answer 33

X 1500