Foundations in Biology Module 2.4 Eukaryotic cell structure

Question 1

Define a cell

Answer 1

the basic unit of all living things

Question 2

What are the 2 types of cells

Answer 2

• Eukaryotic cell
• Prokaryotic cell

Question 3

What is a prokaryotic cell

Answer 3

Single-celled organisms which contain a simple structure

Question 4

Example of prokaryotic cell

Answer 4

Bacteria

Question 5

What is a eukaryotic cell

Answer 5

Multicellular organisms which have a complicated internal structure
Contain membrane-bound organelles

Question 6

Examples of eukaryotic cells

Answer 6

Animal, plant and fungi

Question 7

Define metabolism

Answer 7

All the chemical reactions that take place in an organism

Question 8

What is the role of the rough endoplasmic reticulum (RER)

Answer 8

Has ribosomes bound to the surface
- Is responsible for the synthesise and transport of proteins

Question 9

What is the role of the mitochondria

Answer 9

The site of the final stage of cellular respiration, where energy is released in the form of ATP.
Consists of a double membrane

Question 10

What are the 4 main features of the mitochondria

Answer 10

• outer membrane
• inner membrane (highly folded)
• cristae (folds)
• matrix(fluid)

Question 11

What does the inner membrane of mitochondria contain

Answer 11

Enzymes that are used in aerobic respiration

Question 12

What is the name of DNA found in the mitochondria

Answer 12

Mitochondrial DNA

Question 13

What is the role of the nucleolus

Answer 13

Area within the nucleus which is responsible for producing ribosomes
- It is composed of proteins and RNA

Question 14

In the nucleolus, what is RNA used for

Answer 14

To make ribosomal RNA(rRNA)

Question 15

When is the nucleolus visible

Answer 15

When cells are preparing to divide

Question 16

What is the role of the cytoplasm

Answer 16

• Where chemical reactions take place
• Contains cytoskeleton

Question 17

What is the cytoskeleton and what is it’s role in the cell

Answer 17

A network of fibres necessary for shape and stability of the cell
- It controls cell movement and the movement of organelles within cells.

Question 18

What 4 things does the cytoskeleton consist of

Answer 18

• Microfilaments
• Microtubules
• Intermediate fibres
• Centrioles

Question 19

What are microfilaments

Answer 19

contractible fibres formed from the protein actin

Question 20

What is the role of microfilaments

Answer 20

• They are responsible for cell movement and cell contraction during cytokinesis

Question 21

What are microtubules and what is their role

Answer 21

Globular tubulin proteins polymerise to form tubes which are used to form a scaffold-like structure that determines the shape of the cell.

They act as tracks for movement of organelles including vesicles

Question 22

What are spindle fibres composed of

Answer 22

Microtubules

Question 23

What is the role of intermediate fibres

Answer 23

they give mechanical strength to cells and help maintain their integrity

Question 24

What is the role of the cell-surface membrane

Answer 24

It is selectively permeable
- It controls the movement of substances into and out of the cell and organelles
- controls which substances enter and exit cells

Question 25

What are vesicles and what is their role in the cell

Answer 25

Sacs that have storage and transport roles - transport materials inside the cell

Question 26

What do lysosomes contain

Answer 26

Hydrolytic enzymes

Question 27

What is the role of lysosomes

Answer 27

The breaking down of waste material in the cell, including old organelles

Question 28

In the immune system why are lysosomes important

Answer 28

They break down pathogens ingested by phagocytic cells

Question 29

What organelle is involved in programmed cell death/apoptosis

Answer 29

lysosomes

Question 30

What are centrioles composed of

Answer 30

microtubules

Question 31

What are the roles of the centrioles

Answer 31

- 2 associated centrioles form the centrosome which assemble and organise spindle fibres in cell division - Organisms with cilia and flagella - centrioles position them

Question 32

What is the role of the golgi apparatus

Answer 32

It is formed by cisternae - It modifies proteins and lipids and packages them into vesicles

Question 33

What is the role of the nucleus

Answer 33

- Contains coded genetic information in the form of DNA molecules - DNA directs the synthesis of all proteins required in the cell - DNA controls the metabolic activities of the cell

Question 34

Where is DNA found in the nucleus

Answer 34

Nuclear envelope is a double-membrane that protects DNA from damage in the cytoplasm

Question 35

What does the nuclear envelope contain that enables molecules to move into and out of the nucleus

Answer 35

Nuclear pores

Question 36

How is chromatin formed

Answer 36

DNA associates with histones (protein)

Question 37

How are chromosomes formed

Answer 37

Chromatin coils and condenses

Question 38

What is the role of the smooth endoplasmic reticulum(SER)

Answer 38

The site of lipid and carbohydrate synthesis and storage

Question 39

What is the role of ribosomes

Answer 39

The site of protein synthesis

Question 40

What are ribosomes constructed by

Answer 40

RNA molecules which are made in the nucleolus

Question 41

What 2 organelles contain their own ribosomes

Answer 41

Mitochondria and chloroplast

Question 42

What is the process of protein production

Answer 42

1. Proteins synthesised on the ribosomes on the RER. Passed into it's cisternae and packaged into vesicles. 2. Vesicles containing proteins move towards the golgi appparatus 3. Vesicles fuse with the golgi apparatus. Proteins are modified and repackaged into vesicles 4. Vesicles(secretory) fuse with the cell-surface membrane releasing contents via exocytosis

Question 43

What is the role of the flagella(whip-like)

Answer 43

Enables cells mobility

Question 44

How can the flagella act as a sensory organelle

Answer 44

It can detect chemical changes in a cells environment

Question 45

What are the 2 types of cilia(hair-like)

Answer 45

Stationary cilia Mobile cilia

Question 46

Where can stationary cilia be found

Answer 46

The surface of cells

Question 46

Where are stationary cilia important

Answer 46

Sensory organs e.g. the nose

Question 47

What is the role of mobile cilia

Answer 47

It beats in a rhythmic manner, creating a current, causing fluids/objects adjacent to the cell to move e.g. in the trachea to move mucus away from the lungs

Question 48

What is the 9+2 arrangement of a cilium( singular of Cilia)

Answer 48

- 2 central microtubules - 9 microtubules surrounding the 2 central microtubules

Question 49

What causes the cilia to move in a beating motion

Answer 49

The pairs of parallel microtubules sliding over each other