Eukaryotic Cell - Mitochondria and Centrioles - Part 4

What are the parts inside the mitochondria?

• Outer membrane

• Intermembrane space

• Inner membrane

• Crista (singular)

• 70s Ribosomes

• DNA circle

• Matrix

What can mitochondria do?

move, change shape and divide

How many membranes do mitochondria have?

double membrane, or envelope

1. What is one function of mitochondria

2. What is it used to make

1. site of aerobic respiration/production of ATP

2. used to make certain proteins, particularly enzymes

Since mitochondria contain its own supply of DNA, what is the mitochondrial DNA identical to?

our mothers

Where is mitochondria found?

in animal and plant cells

How is mitochondria like an envelope?

inner membrane folded to form finger like cristae

What does this increase and why?

• increase surface area

to maximize surface available for enzyme attachment

Where is ATP made?

in the folds that is called cristae

Where does the cristae project into?

the interior solution called matrix

1. What is the matrix also involved in?

2. What is this stage called?

1. Aerobic respiration

2. Krebs cycle

1. Describe the matrix?

2. What does the matrix contain?

3. Why does it contain these?

1. semi rigid

2. proteins, lipids, DNA and enzymes

3. required for respiration

What does the outer membrane control?

the entry and exit from the organelles of material

Another function of mitochondria?

Synthesis of lipids

1. Mitochondria are found in abundance in cells that are….?

2. Example of 2 cells?

1. Metabolically active

2. Muscle and Epithelial cells

Where are centrioles found in the cells?

just outside the nucleus

1. Describe centrioles

2. What are the length of centrioles?

• 2 centrioles, at right angles to each other

• small hollow cylinders

2. 0.4µm long

if cells have 1 centriole visible what won’t happen?

the cell is not gonna divide

What happens just before cell division?

the centrioles divide

Centrioles don’t divide in what cell?

plant cells

Function of centrioles?

they make and organise tiny microtubules.

1. What are these microtubules made of?

2. What are the used for?

1. Made of protein called tubulin.

2. to grow the spindle fibres for nuclear division

1. Another function of centrioles?

2. How do centrioles do this?

1. Separation of chromosomes during cell division

2. they move them around and pull them to opposite ends of the cell