Basic Cells and Organelles

Question 1

What is the name for the area of the plasma membrane where proteins involved in cell signalling are concentrated?

Answer 1

Lipid rafts

Question 2

What is the name of the carbohydrate covering which exists on all cells?

Answer 2

Glycocalyx

Question 3

What is the function of carbohydrates in the plasma membrane?

Answer 3

To allow cells to be recognised

Question 4

The phospholipids in the plasma membrane are amphipathic. What does this mean?

Answer 4

They have both hydrophobic and hydrophilic parts

Question 5

Which organelle is continuous with the outer membrane of the nucleus?

Answer 5

Rough endoplasmic reticulum.

Question 6

What is the name of the scaffold of intermediate filaments which attached to the inner nuclear membrane?

Answer 6

Nuclear lamina

Question 7

Where does ribosomal RNA synthesis take place?

Answer 7

Nucleolus

Question 8

How do molecules travel in and out of the nucleus?

Answer 8

They travel via the nuclear pores.

Question 9

Where does the Citric acid cycle of aerobic respiration take place?

Answer 9

The mitochondria

Question 10

What is the function of the outer membrane of mitochondria?

Answer 10

The outer membrane is selectively permeable to allow the passage of some molecules - such as pyruvate which is needed for respiration - into the cell.

Question 11

What is the name of the folds in the inner mitochondrial membrane which are useful in the electron transport chain?

Answer 11

Christae

Question 12

What is the name of the part of the mitochondria which holds the enzymes which are involved in the citric acid cycle?

Answer 12

Matrix

Question 13

The intermembrane space of the mitochondria is important in which process?

Answer 13

The electron transport chain

Question 14

At what organelle in the cell does lipid synthesis and calcium storage occur?

Answer 14

Smooth ER

Question 15

Which organelle is often referred to as the ‘post office’ of the cell?

Answer 15

Golgi

Question 16

As proteins move through the Golgi stack they undergo enzymatic modification. What is the purpose of this modification?

Answer 16

To label proteins for their specific destination in the cell

Question 17

Which organelle is involved in bile synthesis?

Answer 17

Peroxisome

Question 18

What is the function of the lysosome?

Answer 18

To degrade defective/old organelles, macromolecules and particles

Question 19

What is the function if endosomes?

Answer 19

They deliver molecules from the plasma membrane to the lysosome and will fuse with the lysosome to deliver their contents.

Question 20

What is the function of the cytoskeleton?

Answer 20

Maintain correct cell shape
Support fragile plasma membrane
Provides mechanical linkages to help cell bear stress
Facilitates the movement of organelles
Allows the cell to adopt specific behaviours e.g. Growth, migration, division

Question 21

What are the three classes of filamentous protein which make up the cytoskeleton?

Answer 21

Microtubules
Microfilaments
Intermediate Filaments

Question 22

What monomers are microtubules composed of?

Answer 22

Tubulins

Question 23

Actin comprises which type class of filamentous protein of the cytoskeleton?

Answer 23

Microfilament

Question 24

Name some of the proteins which intermediate filaments can be composed of.

Answer 24

Lamins
Keratin
Desmin
Vimentin

Question 25

Which protein class of the cytoskeleton is not associated with motor proteins?

Answer 25

Intermediate filaments

Question 26

Dynein and kinesin are motor proteins associated with...?

Answer 26

Microtubules

Question 27

Myosin is a motor protein associated with...?

Answer 27

Microfilaments

Question 28

Which cytoskeletal element participates in cell extension and motility in terms of lamellipodia and filopodia?

Answer 28

Microfilaments

Question 29

Cells (such as those of the skin) which require a lot of strength will often have a lot of which cytoskeletal component?

Answer 29

Intermediate filaments

Question 30

What is the name of the main microtubule organising centre?

Answer 30

Centrosome

Question 31

What cytoskeletal component is particularly important in the motility of cilia and flagellum?

Answer 31

Microtubules

Question 32

Which motor protein moves cargo away from the centrosome and which moves cargo towards the centrosome?

Answer 32

Away - kinesin | Towards - dynein

Question 33

The aggregation of cells and integration of function is made possible by...?

Answer 33

Cellular junctions

Question 34

What are cellular junctions?

Answer 34

Transmembrane proteins which connect the plasma membrane of a cell to adjacent cells, the basement membrane or the cytoskeleton.

Question 35

What are the three types of cellular junction?

Answer 35

Anchoring junction Occluding or Tight junction Communication or GAP junction

Question 36

What are the four types of anchoring junction?

Answer 36

Adherens junction Focal Adhesion Desmosome Hemidesmosome

Question 37

Between what do adherens junctions provide a contact and to what element of the cytoskelton do they connect?

Answer 37

Provide contact between two adjacent cells Connect to actin cytoskeleton

Question 38

Between what do desmosomes provide a contact and to what element of the cytoskelton do they connect?

Answer 38

Provide contact between two adjacent cells | Connect to intermediate filament network.

Question 39

Between what do hemidesmosomes provide a contact and to what element of the cytoskelton do they connect?

Answer 39

Provides contact between a cell and the extracellular matrix | Connect to intermediate filament network

Question 40

Between what do focal adhesions provide a contact and to what element of the cytoskelton do they connect?

Answer 40

Provide a contact between the cell and the extracellular matrix Bind to the actin cytoskelton

Question 41

Between what do tight junctions provide a contact and to what element of the cytoskelton do they connect?

Answer 41

Provide contact between two adjacent cells | Connect to actin cytoskeleton

Question 42

What is the function of a GAP junction?

Answer 42

Connect the cytoplasm of adjacent cells to allow the passage of inorganic ions and small molecules between cells

Question 43

What type of cell is likely to have an enriched amount of mitochondria?

Answer 43

Spermatozoa

Question 44

The sarcoplasmic reticulum is a specialised organelle of what type of cell?

Answer 44

Muscle cell

Question 45

What components are tight junctions made of?

Answer 45

Claudins

Question 46

What components are adherins junctions made of?

Answer 46

Cadherins

Question 47

What components are desomosomes made up of?

Answer 47

Desmosomal cadherins

Question 48

What components are hemidesmosomes made up of?

Answer 48

Integrins

Question 49

What components are focal adhesions made up of?

Answer 49

Integrins

Question 50

What components are GAP junctions made up of?

Answer 50

Connexins

Question 51

Vohwinkel syndrome is a result of a mutation in which protein?

Answer 51

Connexin 26 which comprises gap junctions

Question 52

Tay sachs disease destroys neurons due to a problem with which organelle?

Answer 52

Lysosome

Question 53

What organelle is particularly enhanced in leydig cells and hepatocytes?

Answer 53

Smooth ER