Cell structure

Question 1

How are prokaryotic cells different to a eukaryotic cell?

Answer 1

Prokaryotic cells have no membrane-bound organelles

all reactions occur in the cytoplasm

Question 2

What is an example of a prokaryotic cell?

Answer 2

Bacterial cell

Question 3

What extra structures do bacterial cells have?

Answer 3

Cell wall

Capsule

Flagella

Pili, fimbriae

Question 4

How are eukaryotic cells different to a prokaryotic cell?

Answer 4

Have membrane-bound organelles

reactions are organised into these organelles

Question 5

What are some examples of eukaryotic cells?

Answer 5

Animal cells

Plant cells

Question 6

What is the structure of a phospholipid molecule?

Answer 6

Head made up of glycerol, phosphate

Tail made up of two fatty acid chains

Question 7

How do phospholiids react to water? Why?

Answer 7

Are amphipathic - have both hydrophobic and hydrophilic parts

Hydrophilic head because is negatively charged

Hydrophobic tails because are non-polar

Question 8

What arrangements do phospholipids take in water and oil?

Answer 8

Form a monolayer with heads pointing towards water, tails pointing towards oil

Form a bilayer with heads pointing towards water, tails pointing to each other

Question 9

What is the structure of the plasma membrane?

Answer 9

Phospholipid bilayer

proteins embedded in the bilayer

Question 10

What are the types of arrangements of proteins in the plasma membrane? What do they each mean?

Answer 10

Integral - in contact with the hydrophobic core of the bilayer

Peripheral - attached to inner or outer surface of bilayer

Question 11

What is the glycocalyx?

Answer 11

The oligosaccharide and polysaccharide chains on outside of plasma membrane

Question 12

What are the oligosaccharride and polysaccharide chains in the glycoclayx attached to? What does this form?

Answer 12

Attached to lipid
forms glycolipid

Attached to protein
forms glycoprotein

Question 13

What are the functions of the plasma membrane?

Answer 13

Selective permeability

Exocytosis, endocytosis

Signal transduction

Question 14

What is selective permeability?

Answer 14

Lets some molecules through it

but not others

Question 15

What does the fluid mosaic model of the plasma membrane mean?

Answer 15

Fluid refers to the phospholipid bilayer being flexible

Mosaic refers to the proteins embedded in the phospholipid bilayer

Question 16

What is the shape of rough endoplasmic reticulum?

Answer 16

Flat cisternae

Question 17

What is attached to rough endoplasmic reticulum?

Answer 17

Ribosomes

Question 18

What is the shape of smooth endoplasmic reticulum?

Answer 18

Tubular shape

Question 19

Are ribosomes attached to smooth endoplasmic reticulum?

Answer 19

No

Question 20

What are the functions of smooth endoplasmic reticulum?

Answer 20

Lipid synthesis

Steroid synthesis

Question 21

Where is smooth endoplasmic reticulum abundant in cells?

Answer 21

Liver

Adrenal glands

Ovaries, testes

Question 22

What is the function of ribosomes?

Answer 22

Protein synthesis

Question 23

Where are ribosomes located in the cell? Where do the proteins they produce go?

Answer 23

Cytoplasm, proteins remain there

Attached to rough endoplasmic reticulum, proteins pushed into rough endoplasmic reticulum

Question 24

What are the two faces of the Golgi apparatus?

Answer 24

Cis face

Trans face

Question 25

What does the cis face of the Golgi apparatus do?

Answer 25

Recieves transport vesicles from ER | fuses with them

Question 26

What does the trans face of the Golgi apparatus do?

Answer 26

Secretory vesicles bud off the trans face | move towards plasma membrane

Question 27

What is the function of the Golgi apparatus?

Answer 27

Modify sort concentrate package proteins synthesised on the rough endoplasmic reticulum

Question 28

How do primary and secondary lysosomes look different under a microscope?

Answer 28

Primary appears black Secondary appears grey

Question 29

Where do lysosomes come from?

Answer 29

The Golgi apparatus trans face

Question 30

What do lysosomes contain? Give some examples

Answer 30

Hydrolytic enzymes - proteases - lipases - glycosidases

Question 31

What is the pH inside a lysosome? How is this brought about?

Answer 31

pH = 5 hydrogen ion pump on membrane of lysosome moves hydrogen ions into the lysosome using energy from ATP -----> ADP + Pi

Question 32

What is the function of lysosomes?

Answer 32

Fuse with material needing to be digested | break it down

Question 33

What sort of materials do lysosomes digest? In what processes?

Answer 33

Digest bacteria in phagocytosis Digest cell's own organelles in autophagy

Question 34

What types of cells are rich in peroxisomes?

Answer 34

Liver cells Kidney cells

Question 35

What is the function of peroxisomes in liver and kidney cells?

Answer 35

Detoxify molecules | e.g. alcohol

Question 36

How do peroxisomes detoxify molecules such as alcohol?

Answer 36

Oxidise them to form hydrogen peroxide | react them with hydrogen peroxide to form water

Question 37

What is the structure of a mitochondrion?

Answer 37

Double membrane - inner and outer intermembrane space between the two Inner membrane is folded into cristae Matrix fills the space inside the inner membrane

Question 38

What does the matrix contain?

Answer 38

Enzymes Mitochondrial DNA

Question 39

What does the inner membrane contain? Give an example

Answer 39

Enzymes for electron transport chain, oxidative phosphorylation e.g. ATP synthase

Question 40

What is the function of mitochondria?

Answer 40

Release energy by oxidative phosphorylation

Question 41

What are some examples of cells rich in mitochondria? Why?

Answer 41

Cardiac muscle cells Sperm cells because they require lots of energy

Question 42

Where are mitochondria located in sperm cells?

Answer 42

Wrapped around the tail

Question 43

What can mitochondria do because they contain their own DNA?

Answer 43

Can divide independently

Question 44

What is the endosymbiotic theory?

Answer 44

Aerobic bacteria taken up into anaerobic cell | aerobic bacteria developed into mitochondria

Question 45

What supports the endosymbiotic theory?

Answer 45

DNA and division of mitochondria is similar to bacteria

Question 46

How are mitochondria inherited?

Answer 46

From mother to offspring

Question 47

How are actin filaments distributed in the cell?

Answer 47

Cortical distribution - meaning edges

Question 48

What type of cell are intermediate filaments common in?

Answer 48

Epithelial cells

Question 49

What is the function if intermediate filaments?

Answer 49

Form a supporting meshwork

Question 50

Where are intermediate filaments located in the cell?

Answer 50

Cytoplasm Beneath inner nuclear membrane

Question 51

Intermediate filaments beneath the inner nuclear membrane is called what?

Answer 51

The nuclear lamina

Question 52

What is the structure of microtubules?

Answer 52

Hollow cylinders | made up of protein tubulin

Question 53

Where are microtubules located in the cell?

Answer 53

In movable structures e.g. cilia, flagella mitotic spindle

Question 54

Where do microtubules arise from in ciliated cells?

Answer 54

Basal bodies

Question 55

Where do microtubules arise from in dividing cells?

Answer 55

Centrosome

Question 56

How are microtubules arranged in cilia or flagella?

Answer 56

9+2 arrangement 9 fused pairs of microtubules around the egde 2 unfused microtubules in the centre

Question 58

Arrange the following filaments in order from thickest to thinnest: - intermediate filaments - microtubules - actin filaments

Answer 58

Actin filaments Intermediate filaments Microtubules

Question 59

Where are mitochondria located in cardiac muscle cells?

Answer 59

Between myofibrils