(2.1) Cell structure

Question 1

What is the maximum resolution of a light microscope?

Answer 1

0.2 micro metres

Question 2

Define resolution

Answer 2

The ability of a microscope to distinguish details of a sample or specimen

Question 3

What is the maximum resolution of an electron microscope?

Answer 3

0.1 nano metres

Question 4

What is the role of the ribosomes on the RER?

Answer 4

Synthesises proteins that will be exported outside of the cell

Question 5

What is the function of the RER?

Answer 5

• provides a large surface area of a ribosome
• An intracellular transport system - the cisternae form channels for transporting substances to different areas of the cell

Question 6

What is the role of the SER?

Answer 6

sight of lipid and steroid synthesis

Question 7

Describe the structure of the nucleus?

Answer 7

• a nuclear envelope with pores creating a membrane bound organelle
• nucleolus
• nucleus

Question 8

What is the function of the nucleolus?

Answer 8

• Contains RNA
• Makes ribosomes

Question 9

How do dissolved substances and ribosomes leave the nucleus?

Answer 9

The outer and inner nuclear membranes fuse together

Question 10

How do larger substances e.g. mRNA leave the nucleus?

Answer 10

Through the nuclear pores

Question 11

Where are an organism’s genes stored?

Answer 11

• in chromosomes
• chromatin wrapped in histone proteins

Question 12

What is the role of the nucleus?

Answer 12

• control centre of the cell
• stores the organism’s genome
• transmits genetic information
• provides instructions for protein synthesis

Question 13

What is the role of the golgi apparatus?

Answer 13

• receives/modifies proteins
• packages and organises where proteins need to go

Question 14

How can the golgi apparatus modify proteins?

Answer 14

• adding a sugar
• adding lipid molecules
• being folded into their 3D shape

Question 15

What are glycoproteins and how are they formed?

Answer 15

When the golgi apparatus modifies a protein by adding a sugar

Question 16

What are lipoproteins and how are the formed?

Answer 16

When the golgi apparatus modifies a protein by adding a lipid

Question 17

What is the function of a mitochodria?

Answer 17

The site of aerobic respiration

Question 18

What is the function of independent ribosomes?

Answer 18

Primarily the site of assembly of proteins to be used outside of the cell

Question 19

What is the function of centrioles?

Answer 19

• creates spindle (threads of tubulin)
• centrioles multiply/line up beneath the cell surface membrane and microtubules sprout outwards from each centriole to create cilium and undulipodium

Question 20

What is the role of lysosomes?

Answer 20

Contain enzymes for digestion

Question 21

What is the purpose of the cell wall?

Answer 21

Structural support so that the cell is resistant to the vacuole pushing against the plasma membrane, otherwise the cell would burst

Question 22

What is the cell wall permeable to?

Answer 22

Water

Question 23

What is the function of the chloroplast?

Answer 23

It is the site of photosynthesis

Question 24

What is the structure of the chloroplast?

Answer 24

• outer membrane
• inner membrane
• intermembrane space
• granum
• thylakoids
• intergranal lamellae
• stroma

Question 25

What are granum?

Answer 25

Stacks of thylakoids

Question 26

What is the function of thylakoids?

Answer 26

Where light dependent photosynthesis is carried out, creating chlorophyll

Question 27

What is the function of the stroma?

Answer 27

Where light independent photosynthesis is carried out with CO2 fixing

Question 28

What is the function of the amyloplast?

Answer 28

Stores starch

Question 29

What is the function of the vacuole?

Answer 29

- filled with sap and water - maintains turgor pressure - regulates osmosis

Question 30

What are cisternae?

Answer 30

Fluid filled cavities in the endoplasmic reticulums

Question 31

What is carried out at the mitochondrial matrix?

Answer 31

- where the krebs cycle takes place - CO2 is produced

Question 32

What is carried out at the cristae in the mitochondria?

Answer 32

- Oxidative phosphorylation - ATP is generated

Question 33

What are the intermembrane spaces in the chloroplast and mitochondria?

Answer 33

Space between the inner and outer membrane

Question 34

What are the mitochondrial matrix?

Answer 34

Any liquid space

Question 35

What do most antibiotics target in bacteria and why?

Answer 35

Target the bacterial cell wall as once it is broken down the bacterium bursts under the osmotic pressure

Question 36

What are pili?

Answer 36

- Hair like projections on the bacterial cell surface - Allow cell communication and horizontal gene transfer

Question 37

What is horizontal gene transfer?

Answer 37

Where bacterium cells interlock pili and can pass genetic information in plasmids

Question 38

What are plasmids?

Answer 38

Smaller loops of DNA in bacterial cells

Question 39

Why is horizontal gene transfer prominent when it comes to antibiotic resistance?

Answer 39

The plasmids can be passed which store information about the antibiotics which can cause more of the bacterial cells to become resistant to it

Question 40

What is different between eukaryotic and prokaryotic cells?

Answer 40

- prokaryotes are smaller - Naked DNA with no histone proteins - no nucleus - no membrane bound organelles - smaller ribosomes - flagella vs cilia/undulipodium

Question 41

What is the difference between flagella and undulipodium?

Answer 41

Flagella are like propellers and undulipodium move like waves

Question 42

What is the triangle for calculating magnification?

Answer 42

Image ------------------------------------- actual | magnification

Question 43

What is the bacteria cell wall made up of?

Answer 43

Peptidoglycan

Question 44

What is peptidoglycan a combination of?

Answer 44

Peptides and Carbohydrates

Question 45

Describe the process of transcription and translation

Answer 45

1. A gene moves out through the nuclear pores into the cytoplasm in the form of mRNA 2. mRNA binds to ribosomes on the RER and translation occurs 3. A new protein is made and packaged by the pinching of cisternae 4. The vesicle travels to the golgi apparatus where the protein is modified 5. The vesicle is then secreted and travels towards the plasma membrane 6. The vesicle fuses with the cells surface membrane and is secreted via exocytosis