Organelles

Question 1

What is chromatin?

Answer 1

Genetic material made up of DNA and proteins

Question 2

What are the 2 types of chromatin?

Answer 2

Heterochromatin and Euchromatin

Question 3

What type of chromatin is used for gene expression and why?

Answer 3

Euchromatin as the DNA is not tightly wound so it is easy for transcription to occur

Question 4

Why can’t heterochromatin be involved in gene expression?

Answer 4

The DNA is tightly wrapped around proteins to form solenoids

Question 5

What are the features of a prokaryotic cell?

Answer 5

No nucleus, cell wall, lacks most organelles, reactions take place in one compartment as there are no internal membranes

Question 6

What are the functions of the plasmalemma? (5)

Answer 6

Allows for endocytosis and exocytosis 
Intercellular adhesion
Signal transduction 
Recognition 
Selective permeability

Question 7

What are the 2 faces of the Golgi called?

Answer 7

The Formed/Cis face (where proteins are received) and the Budding/Trans face (where proteins are secreted)

Question 8

What is the function of the Golgi?

Answer 8

Modifies, sorts and packages proteins

Question 9

What are lysosomes?

Answer 9

Vesicles generated by the Golgi containing hydrolytic enzymes

Question 10

What is the cell coat of lysosomes made up of?

Answer 10

Polysaccharides and oligosaccharides which stop the lysosome digesting everything

Question 11

What is the cell coat of a lysosome called?

Answer 11

Glycocalyx

Question 12

What are peroxisomes?

Answer 12

Vesicles that detoxify compounds using catalase to oxidise toxic molecules

Question 13

Where are peroxisomes most commonly found?

Answer 13

Liver and Kidney

Question 14

What are the 3 types of filaments in the cytoskeleton?

Answer 14

Actin filaments, intermediate filaments and microtubules

Question 15

What are microtubules made up of?

Answer 15

Tubulin

Question 16

Where are microtubules found?

Answer 16

Where structures move e.g. Cilia, flagella and mitotic spindle

Question 17

Which is the biggest filament in the cytoskeleton?

Answer 17

Microtubules

Question 18

What is the mitochondria the site of?

Answer 18

ATP/energy production

Question 19

From whom do you inherit your mitochondria?

Answer 19

Mother

Question 20

What do mitochondria contain?

Answer 20

They’re own genome, enzymes for oxidative reaction and ribosomes

Question 21

What is a secondary lysosome?

Answer 21

A lysosome that has already fused with a bacteria and contains its residue

Question 22

What is the function of the SER?

Answer 22

Lipid production

Question 23

What is the function of the RER?

Answer 23

The ribosome on the outside is where mRNA is translated.

Question 24

What is the difference in shape between the RER and the SER?

Answer 24

The RER compromises of flat cisterna whereas the SER is tubular not flat

Question 25

What is an amphipathic molecule?

Answer 25

One which has polar and non polar parts

Question 26

What is the structure of a phospholipid molecule?

Answer 26

Polar, hydrophilic head and a non polar, hydrophobic fatty acid tail

Question 27

Why is it useful for eucaryotic cells to be compartmentalised?

Answer 27

So that reactions don't interfere with each other meaning that many reactions can occur

Question 28

What is the hydrophilic part of a phospholipid molecule and what is the hydrophobic part?

Answer 28

Hydrophilic=polar head | Hydrophobic = nonpolar, fatty acid tail

Question 29

What is the word that means lipid production?

Answer 29

Steriodogenesis

Question 30

What does constitutive secretion mean?

Answer 30

The proteins are constantly released

Question 31

Why are lysosomes acidic on the inside?

Answer 31

As they contain many hydrolytic enzymes

Question 32

How could you tell the difference between a TEM of a lysosome and a peroxisome?

Answer 32

Peroxisomes are darker

Question 33

What features do steroidogenic cells have?

Answer 33

Lots of SER to produce steroids

Question 34

What is the nucleolus?

Answer 34

It is made up of 5 uncondensed chromosomes forming a circular area of heterochromatin that contains sequences of ribosomal DNA