Cell and Tissue Structure

Question 1

what can all cells do? (7)

Answer 1

grow
divide
respire
communicate
excrete
respond to env
sometimes move

Question 2

how many different cell types?

Answer 2

270

Question 3

why study cells in medicine?

Answer 3

• all disease has a cellular aspect
• treatment of disease focuses on the cell

Question 4

why have different organelles?

Answer 4

division of labour -> increased efficiency and complexity = ALLOWS MORE FUNCTIONS

Question 5

what is the function of the nucleus?

Answer 5

-storage of DNA
-expression of DNA
-Replication of DNA
-

Question 6

draw the structure of the nucleus

Answer 6

Question 7

how is DNA stored in nucleus?

describe the structure of nucleus

Answer 7

1. as chromatin
2. nucelus is surroundered by double membrane: nuclear envelope. nuclear envelope contains nuclear pores.

Question 8

what is the role of the nucleur envelope?

Answer 8

seperates the nucleus from the rest of the cytoplasm

Question 9

how many layers does the nucleur envelope have?

Answer 9

double layer (inner and outer membrane) BUT, underneath the double layer is the nuclear lamina

Question 10

what is the role of the nuclear lamina?

Answer 10

made of meshwork of fibres that keeps the structure of the nucleus

Question 11

what goes in / out of the nuclear pores?

Answer 11

ribosomal RNA, mRNA, proteins, carbs

Question 12

what is this?

Answer 12

nuclear pore

Question 13

what is laminopathies?

explain an example of one

Answer 13

diseases of the nuclear lamina - there 8

Hutchinson-Gilford Progeria Syndrome - premature ageing - nucleus cannot divide properly. weakening of the nuclear lamina

Question 14

what is the nucleolus?

what is its function?

Answer 14

dark sphere of the nucleus

function: ribosomal (r) RNA transcription, rRNA processing and ribsomal assembly

Question 15

what are heterochromatin and euchromatin?

Answer 15

heterochromatin:

• tightly packed / condensed DNA
• generally transcriptionally inactive (repressed)

euchromatin:

• more dispersed
• less densely activated
• transcriptionally active DNA

Question 16

which here is euchromatin and which is heterochromatin and nucleolus?

Answer 16

heterochromatin - tightly packed parts

euchromatin is in on th edge / less bound

nucleolus - in the middle

Question 17

if chromatins are tightly packed - generally means they are..?why?

Answer 17

not transcriptionally active, because not open for transcriptional machinery to come in

Question 18

label these

Answer 18

Question 19

whats the difference between euchromatin and heterochromatin?

Question 20

what are emerin and lamin?

Answer 20

inner nuclear proteins

Question 21

what do emerin and lamin defects lead to?

Answer 21

premature aging syndromes, muscular dystrophy, and cardiomyopathy

Question 22

what are the subunits of ribosomes?

Answer 22

60s or 40s

Question 23

what happens if get a defect in the RER? what diseases can this lead to?

Answer 23

• abnormality in protein folding

Alzheimers, CF

Question 24

where do lysosomes originate from?

functions of lysosomes?

diseases of lysosomes?

Answer 24

• originate from Golgi
• functions: contain digestive enzymes
• diseases: lysosome storage diseases - Tay-Sachs disease

Question 25

where do peroxisomes orginate?

function?

disease?

Answer 25

orginate at RER

function: metabolise fatty acids, detoxification (liver and kindey). contain enzyme catalase: breaks down hydrogen peroxide
diseases: hydrogen peroxide build up - e.g. Zellweger syndrome

Question 26

how many mitchondrial proteins and mitochondrial genes are there?

Answer 26

-1500 mitochondrial proteins

37 mitochondrial geness

Question 27

diseases associated with mitchondria?

Answer 27

neuro / muscular dysptrohies (cuz need lots of energy)