2: cell structures

Question 1

what is an organelle?

Answer 1

a sub-cellular structure that has one or more jobs to perform in the cell

Question 2

what a cell membrane?

Answer 2

a very thin layer of protein and fat

Question 3

what is the purpose of the cell membrane?

Answer 3

• controls what enters and leaves the cell
• separates the contents of the cell from the environment

Question 4

what is a cell wall?

Answer 4

a structural layer made of cellulose, just outside the cell membrane

Question 5

what does the cell wall do?

Answer 5

• provides support
• gives a definite shape
• prevents cell from bursting

Question 6

what is a cytoplasm?

Answer 6

a clear jelly made up of water

Question 7

what is the purpose of the cytoplasm?

Answer 7

place where metabolic reactions take place

Question 8

what are vacuoles?

Answer 8

a fluid filled space

Question 9

what is the purpose of the vacuole?

Answer 9

• contains cell sap
• storage of substances
• storage of waste products

Question 10

what is the nucleus?

Answer 10

the largest organelle

Question 11

what does the nucleus do?

Answer 11

• contains the genetic material which makes up genes on chromosomes
• protein synthesis, mitosis, cell activities

Question 12

list the properties of the nucleus

Answer 12

• surrounded by nuclear envelope perforated by nuclear pores
• contains chromatin
• contains nucleolus

Question 13

what do the nuclear pores of the nuclear envelope do?

Answer 13

allows and controls exchange between nucleus and cytoplasm

Question 14

what is the chromatin?

Answer 14

long, thin, loosely coiled packs of DNA that condense to make chromosomes

Question 15

what is the nucleolus?

Answer 15

the nucleolus is a spherical structure found in the nucleus whose primary function is to produce ribosomes

Question 16

what is the endoplasmic reticulum (ER)?

Answer 16

interconnected tubes and flattened sacs that begin at the nucleus and wind through the cytoplasm

Question 17

what is the main difference between rough ER and smooth ER?

Answer 17

rough ER is covered with many ribosomes

Question 18

what is the golgi body?

Answer 18

vesicles that have broken off from the ER and have joined together

Question 19

what does the golgi body do?

Answer 19

it collects, processes, and sorts molecules

Question 20

what does RER do?

Answer 20

transports and modifies proteins

Question 21

what does SER do?

Answer 21

synthesises and transports lipids

Question 22

what are ribosomes?

Answer 22

structures that combine amino acids to form proteins

Question 23

where can ribosomes be found?

Answer 23

attached to the ER or lying freely in the cytoplasm

Question 24

what are lysosomes?

Answer 24

spherical sacs/vesicles/vacuoles that contain enzymes

Question 25

what is the function of lysosomes?

Answer 25

- breaks down materials ingested by cells - releases enzymes inside cells

Question 26

what are secretory vesicles?

Answer 26

vesicles released from the golgi body

Question 27

what if the function of the secretory vesicle?

Answer 27

- contains cell products - exports enzymes out of the cell

Question 28

what is a mitochondria?

Answer 28

double membrane-bound organelles

Question 29

what is the function of the mitochondria?

Answer 29

- carry out aerobic respiration - produce ATP

Question 30

what is a chloroplast?

Answer 30

a type of plastid bounded by a double membrane

Question 31

what does the chloroplast do?

Answer 31

produces energy through photosynthesis

Question 32

what do chloroplasts contain?

Answer 32

- chlorophyll - enzymes to make glucose - starch grains

Question 33

list the differences between a typical animal and plant cell? [6]

Answer 33

- plant got cell wall, animal nada - plant got large vacuoles, animal smaller - plant got chloroplast, animal nada - plant cytoplasm less dense, animal dense - plant larger, animal smaller - plant got definite shape, animal irregular

Question 34

what is the plasmid?

Answer 34

smaller circles of DNA

Question 35

what is the pili?

Answer 35

for attachment to other cells or surfaces in sexual reproduction

Question 36

how are new cells produced?

Answer 36

by the division of existing cells

Question 37

what are tissues?

Answer 37

groups of cells that have similar functions

Question 38

what are the 4 main tissue types?

Answer 38

- epithelial - connective - muscle - nervous

Question 39

what does the epithelial tissue group do?

Answer 39

covers and protects surfaces

Question 40

what does the connective tissue group do?

Answer 40

binds and strengthens

Question 41

what does the nervous tissue group do?

Answer 41

transmits nerve impulses

Question 42

what does the muscle tissue group do?

Answer 42

contracts to support and move

Question 43

what does the xylem vessel do?

Answer 43

it transports water and mineralsw

Question 44

what does the phloem vessel do?

Answer 44

transports food

Question 45

what are organs?

Answer 45

groups of different tissues that perform specialised functions

Question 46

what is an organ sustem?

Answer 46

several organs working together to form a specific task

Question 47

what can't be seen on a light microscope?

Answer 47

small organelles like ribosomes

Question 48

what does an electron microscope use?

Answer 48

electron beams

Question 49

what is magnification?

Answer 49

number of times larger an image is compared to the original size of the object

Question 50

what is the formula for magnification?

Answer 50

observed size of image --------------------------------- actual size

Question 51

what is the formula for the linear magnification of a drawing?

Answer 51

size of drawing --------------------- actual size

Question 52

what is the formula for the total magnification?

Answer 52

objective lens x eyepiece lens