Cells Structure

Question 1

What is the function of the Cell Wall?

Answer 1

Gives strength, support and structure
Acts as a carbohydrate store (by varying the amount of cellulose it has)

Question 2

What are Cell Walls made of?

Answer 2

Polysaccharide cellulose in plants
Chitin in fungi
Peptidoglycan in bacteria

Question 3

What are the pores of the Cell Wall called? What do they do?

Answer 3

Plasmodesmata - connect 2 cells together by their cytoplasm - enables exchange and transport of substances

Question 4

What are the parts of the Nucleus?

Answer 4

Chromatin, envelope, pore, nuclear plasma, nucleolus

Question 5

What is the function of the Nucleus?

Answer 5

Stores the genome in the form of chromatin

Question 6

What is Chromatin?

Answer 6

Genetic material composed of DNA wound around histone protein that condense to form chromosome during cell division

Question 7

What is the Nuclear Envelope?

Answer 7

The double membrane surrounding the nucleus that is perforated by pores to allow larger substances to enter/exit

Question 8

What is the Nucleolus?

Answer 8

The densely stained region in the nucleus where RNA is made

Question 9

What is the mitochondria?

Answer 9

The energy generating organelle

Question 10

What are the parts of the mitochondria?

Answer 10

Double membrane, matrix, cristae

Question 11

What does the double membrane of the mitochondria do?

Answer 11

Inner - folds in to form cristae

Question 12

What does the cristae do?

Answer 12

it is coated in enzymes which catalyse the reaction of aerobic respiration to produce ATP

Question 13

What is the Cytoplasm

Answer 13

Comprises of a liquid called cytosol and all the organelles suspended in it

Question 14

What are chloroplasts?

Answer 14

Present in all green plants and use CO2, water and light energy to build sugars

Question 15

What are the parts of a Chloroplast?

Answer 15

Stroma, thylakoid membranes, grana, double membrane

Question 16

What is the stroma?

Answer 16

A liquid which fills up the inside of a chloroplast and surrounds the grana

Question 17

What are grana?

Answer 17

Stacks of thylakoid membranes

Question 18

What are thylakoid membranes

Answer 18

The site of photosynthesis

Question 19

What is the tonoplast

Answer 19

The vacuole membrane

Question 20

What is the cell sap

Answer 20

The watery solution of sugars, enzymes, pigments

Question 21

What do Vacuoles do

Answer 21

Important in keeping the cell turgid

Question 22

What are Endoplasmic Reticulums?

Answer 22

An extensive system of membranes through the cell

Question 23

What are cisternae

Answer 23

double membraned flattened sacs formed by the ER

Question 24

What are cisternae used for?

Answer 24

transport

Question 25

Difference between rough ER and smooth ER

Answer 25

RER - continuous with nuclear envelope and has ribosomes SER - has enzymes and is the production site of lipids, steroids and cholesterol

Question 26

What is the RER used for

Answer 26

Site of protein synthesis

Question 27

Where and what are ribosomes made from

Answer 27

Nucleolus out of ribosomal RNA

Question 28

What is the structure of a ribosome?

Answer 28

Large and small subunits (two sperate units)

Question 29

Location of ribosomes

Answer 29

Some are free and some are attached to RER

Question 30

What do the ribosomes attached to the RER do

Answer 30

synthesise proteins to be transported out

Question 31

What do free ribosomes do?

Answer 31

synthesise proteins to be used in cells

Question 32

What are Golgi apparatus

Answer 32

Stack of flattened, double membraned cisternae constantly being formed at one end from vesicles that bud off from the ER

Question 33

What do Golgi Apparatus do

Answer 33

Modify, sort and package molecules for transport

Question 34

What are some Golgi vesicles

Answer 34

lysosomes

Question 35

What are Lysosomes

Answer 35

sacs surrounded by a single membrane

Question 36

What are Lysosomes produced by

Answer 36

Golgi Apparatus

Question 37

Features of Lysosomes

Answer 37

Low pH and contained hydrolytic (digestive) enzymes

Question 38

What are Lysosomes responsible for

Answer 38

Breakdown of unwanted organelles and foreign matter

Question 39

Where are Lysosomes abundant in

Answer 39

Certain WBC that digest bacteria after phagocytosis

Question 40

Centrioles location (animal cell)

Answer 40

2 outside nucleus

Question 41

Centrioles structure

Answer 41

Hollow cylinders at right angles In triplets

Question 42

What is the cytoskeleton made of

Answer 42

2 types of protein fibre, actin filaments and microtubules

Question 43

Function of the cytoskeleton

Answer 43

Provides mechanical strength Aids transport Aids cell movement

Question 44

What are motor proteins

Answer 44

enzymes that allow the hydrolysis of ATP

Question 45

Structure of Cilia and Undulipodia

Answer 45

Microtubules arranged in a cylinder in a 9+2 formation Cilia -short and abundant - beat rhythmically Undulipodia - long +usually singular + cause cell to move

Question 46

Steps of protein synthesis

Answer 46

1. mRNA copy of gene for insulin is made in nucleus 2. mRNA leaves nucleus through nuclear pore 3. mRNA attaches to ribosome on ER 4. Insulin molecules are 'pinched off' in vesicles to Golgi 5. Vesicle fuses with Golgi 6. Golgi processes and packages insulin molecules for release 7. Packaged molecule are pinched off in vesicles from Golgi to membrane 8. vesicle fuses with cell surface membrane 9. exocytosis

Question 47

What is magnification

Answer 47

the degree to which the size of an image is larger than itself

Question 48

What is resolution

Answer 48

the ability to distinguish between 2 points

Question 49

Types of microscopes

Answer 49

Light microscope Laser scanning microscope Transmission electron microscope Scanning electron microscope

Question 50

Features of a light microscope

Answer 50

magnification up to x1500 res up to 0.2um 4 objective lens and eyepiece

Question 51

Laser scanning microscope features

Answer 51

Laser scans object, image is displayed on screen high res + contrast focus at diff depth multiple images combine to make 3D image used in medicine

Question 52

TEM features

Answer 52

Electrons pass through 2D images mag up to x500,000 res = 0.1nm

Question 53

SEM features

Answer 53

electrons bounce off 3D images Mag up to x100,000 res = 0.1nm