Intro to cells

Question 1

What do ALL cell types possess?

Answer 1

• Cell membrane
• DNA
• Cytoplasm
• Ribosomes

Question 2

What are Prokaryotic cells?

Answer 2

Small and relatively simple in internal structure and have no-membrane bound organelles and no true nucleus

Question 3

What are Eukaryotic cells?

Answer 3

Larger and more complex than prokaryotic cells

Are found in higher animals and plants and contain a nucleus

Question 4

What are the 4 features of a cell membrane?

Answer 4

• Semi-permeable barrier
• Retains most organically produced chemical inside cell
• allows a few molecules across - diffusion, osmosis, active transport
• Communication - receptors on cell surface

Question 5

what is the most common molecule in the cell membrane?

Answer 5

Phospholipid

Question 6

What is cholesterol’s role in the cell membrane?

Answer 6

Provides membrane integrity - prevents lysis

Question 7

What is proteins role in the cell membrane?

Answer 7

Gateway that allows certain molecules into and out of the cell

Question 8

What are the 2 pathologies of cell membranes?

Answer 8

• Sickle cell anaemia
• Thalassemia
  (both caused by defects in haemoglobin)

Question 9

Which type of cell contains a nucleus?

Answer 9

Eukaryotic cells

Question 10

Where is DNA largely restricted to?

Answer 10

The nucleus

Question 11

What does the nuclear envelope do?

Answer 11

Allows RNA and other chemicals to pass through the membrane - but NOT DNA

Question 12

The area where ribosomes are constructed?

Answer 12

The nucleolus

Question 13

Where is the site of transcription?

Answer 13

The nucleus

Question 14

What type of cell are ribosomes found?

Answer 14

BOTH prokaryotes and eukaryotes

Question 15

Which is larger: eukaryotic ribosomes or prokaryotic ribosomes?

Answer 15

Eukaryotic ribosomes

Question 16

What is the structure of a ribosome?

Answer 16

A small and a larger subunit

Question 17

What is the main role of a ribosome?

Answer 17

Protein translation

Question 18

What is a common Ribosomopathies?

Answer 18

Treacher Collins Syndrome - Abnormal craniofacial development

Question 19

What is the main function of the endoplasmic reticulum?

Answer 19

Protein synthesis and transport

Question 20

Where does the rough endoplasmic reticulum connect to?

Answer 20

The nuclear envelope - mRNA is converted to peptide and passed on to rough ER

Question 21

What is the key function of the ROUGH endoplasmic reticulum?

Answer 21

Protein modification and production: lysosomal enzymes, secreted proteins, integral membrane proteins

Question 22

What happens during protein modification and production in the rough ER?

Answer 22

• correct folding: important for function
• Appropriately ‘tagged’ for distribution throughout cell
• Post-translational modifications: structure and function

Question 23

What is the main function of the SMOOTH endoplasmic reticulum?

Answer 23

Manufacture of lipids - specialised functions:

• Liver: glycogen broken down to glucose
• Adrenal cortex: steroid hormone production
• Muscle: Calcium storage in the sarcoplasmic reticulum. Contraction of muscle cells triggered by the orderly release of calcium ions

Question 24

What is meant by the SMOOTH ER ‘detox stop’?

Answer 24

The smooth ER detoxifies a number of organic chemicals, converting them into safer water-soluble products

Question 25

What is ER dysfunction describes as?

Answer 25

Defective folding and processing of proteins

Question 26

Name 3 Neurodegenerative disorders associated with ER dysfunction?

Answer 26

- Alzheimer's - Parkinson's - Epilepsy

Question 27

What is ER dysfunction associated with?

Answer 27

Ageing

Question 28

How do correctly folded proteins move from the ER to the Golgi apparatus?

Answer 28

Via transport vesicles

Question 29

What are the functions of the Golgi apparatus?

Answer 29

- Further modifies proteins - Stores proteins - Packages proteins (thought of as the 'post office' of the cell)

Question 30

What does impaired trafficking of proteins through the Golgi apparatus cause?

Answer 30

Hypomyelinating disorders e.g. cataract

Question 31

What does impaired post-translational capacity in the Golgi apparatus cause?

Answer 31

- Defective glycosylation disorders | - wide spectrum of pathologies that affect multiple organs

Question 32

What does functionality loss due to mutations in proteins that make up the Golgi apparatus cause?

Answer 32

Muscular Dystrophy

Question 33

What are Vacuoles?

Answer 33

- Used as storage areas | - Formed by the fusion of numerous vesicles

Question 34

What are vesicles?

Answer 34

- Much smaller than vacuoles | - Function is transport, within and outside of the cell

Question 35

What are lysosomes?

Answer 35

- Large vesicles formed by the Golgi - Contain hydrolytic enzymes that can destroy the cell - Function in the breakdown of extracellular materials

Question 36

What is the function of mitochondria?

Answer 36

Site of ENERGY RELEASE and ATP formation - The mitochondria is the POWERHOUSE of the cell

Question 37

What are the 2 membranes of the mitochondria?

Answer 37

- Outer - smooth and sieve like | - Inner - folded into CRISTAE: the surfaces on which ATP is generated

Question 38

Name some diseases that mitochondrial dysfunction is associated with?

Answer 38

- Alzheimer's - Parkinson's - Diabetes - Stroke - Cancer

Question 39

What is the cytoplasm?

Answer 39

The material between the cell membrane and the nuclear envelope

Question 40

What is the function of the cytoplasm?

Answer 40

Transport of materials around the cell: cytoplasmic streaming

Question 41

What are the functions of the cytoskeleton?

Answer 41

- Maintains shape of cell - Anchors organelles - Moves cell - Controls internal movement of organelles

Question 42

What do actin monomers do?

Answer 42

- Maintain cell shape - Muscle contraction - Cytoplasmic streaming - Cell division

Question 43

What do Intermediate filaments do?

Answer 43

- Maintain cell shape - Anchor nucleus - Nuclear lamina

Question 44

What do microtubules do?

Answer 44

- Cell motility - Chromosome movement - Organelle movement