Cell organelles

Question 1

When is cell is polarised, what does this mean?

Answer 1

There are spatial differences in structure and function- asymmetric

Question 2

What way does the apical membrane face?

Answer 2

faces the lumen or external environment

Question 3

What way does the basal membrane face?

Answer 3

Facing the basement membrane, or inside of the body

Question 4

What size are Eukaryotes generally?

Answer 4

5 micrometers or more

Question 5

What size are Prokaryotes generally?

Answer 5

1-5 micrometers

Question 6

What does the nucleolus do?

Answer 6

Makes ribosomal RNA

Question 7

What do glycolipids provide in the PM?

Answer 7

provide binding sites for proteins

Question 8

What do oligosaccharides side chains do in the PM?

Answer 8

provide bindings sites for proteins, and act as cell recognition sites

Question 9

Where do you find integral proteins on the PM?

Answer 9

they span the length

Question 10

Where do you find peripheral proteins on the PM?

Answer 10

one side of the lipid bilayer

Question 11

What are the 2 roles of the plasma membrane?

Answer 11

1) mediates communication

2) Regulates transport of solutes

Question 12

Is the head of a phospholipid hydrophobic or hydrophilic?

Answer 12

Hydrophilic

Question 13

What is the hydrophilic head of a phospholipid formed of?

Answer 13

Choline, phosphate and glycerol

Question 14

What are the tails of a phospholipid formed of?

Answer 14

hydrocarbons

Question 15

What makes a hydrocarbon tail of a phospholipid bent?

Answer 15

A CIS double bond

Question 16

Is a phospholipid head polar?

Answer 16

Yes

Question 17

Is a phospholipid tail polar?

Answer 17

no, non polar

Question 18

Adding bent tails to a phospholipid bilayer make it ……. fluid

Answer 18

less

Question 19

Cholesterol makes the phospholipid bilayer more or less fluid

Answer 19

less

Question 20

Why can ethanol pass through a membrane passively ?

Answer 20

Because it is a small molecule and is not charged

Question 21

Water and Urea are only slightly permeable to membranes due to what 2 characteristics?

Answer 21

1) the molecules are small but polar

2) the molecules are uncharged

Question 22

Why is glucose impermeable to the cell surface membrane passively?

Answer 22

it is a large molecule and is polar

Question 23

Why can’t ATP, Proteins and Amino Acids pass through the membrane passively? 2 things

Answer 23

they are charged and polar

Question 24

What do Anchors do as proteins in the membrane?

Answer 24

link intracellular actin filaments to extracellular matrix proteins

Question 25

is the outer membrane of the mitochondria permeable?

Answer 25

Yes

Question 26

Is the inner membrane of the mitochondria permeable?

Answer 26

not so permeable

Question 27

How does the mitochondria make its own proteins?

Answer 27

It has its own DNA

Question 28

In the ETC how is a H ion gradient harvested?>

Answer 28

ATP synthase

Question 29

What is the role of the Golgi apparatus?

Answer 29

to sort, pack and modifiy proteins

Question 30

What is the basic structure of peroxisomes?

Answer 30

cytoplasmic vesicles

Question 31

What do peroxisomes do, and using what process?

Answer 31

Break down ethanol and fatty acids, oxidation

Question 32

What is the basic structure of lysosomes?

Answer 32

cytoplasmic vesicles

Question 33

What is the function of lysosomes?

Answer 33

to digest intracellular bodies using degradative enzymes

Question 34

What does the ER do?

Answer 34

synthesis of lipids and proteins

Question 35

What does the nucleus hold, and what happens there?

Answer 35

DNA, genome and RNA synthesis

Question 36

What do endosomes do?

Answer 36

carry endocytosed material

Question 37

Actins average diameter is?

Answer 37

7nm

Question 38

Actin's role is to.....

Answer 38

aid movement of proteins eg. myosin

Question 39

Actin can be found in which structure of the gut?

Answer 39

microvilli

Question 40

Microtubules' average diameter are?

Answer 40

20nm

Question 41

Microtubules are polymers of what?

Answer 41

Tubulin dimers

Question 42

A centrosome is a type of.....

Answer 42

microtubule

Question 43

The 2 roles of microtubules are too....

Answer 43

Shape a structure and aid movement of proteins | Create a train track system

Question 44

Stem cells are not terminally....

Answer 44

differentiated

Question 45

Do stem cells divide without limit?

Answer 45

yes

Question 46

What does totipotent stem cell mean?

Answer 46

have the capacity to self-renew by dividing and to develop into the three primary germ cell layers of the early embryo and into extra-embryonic tissues such as the placenta

Question 47

What does pluripotent stem cell mean?

Answer 47

capacity to self-renew by dividing and to develop into the three primary germ cell layers of the early embryo and therefore into all cells of the adult body, but not extra-embryonic tissues such as the placenta. MAKE MANY BUT NOT ALL CELL TYPES

Question 48

Most adult stem cells are....

Answer 48

multipotent stem cells

Question 49

what does multipotent stem cells mean?

Answer 49

have the capacity to self-renew by dividing and to develop into multiple specialised cell types present in a specific tissue or organ

Question 50

How do Induced Pluripotent stem cells work?

Answer 50

1) Stem cells are taken from the skin of a patient 2) they are despecialised 3) made into part you want

Question 51

What is an advantage of using Induced Pluripotent stem cells?

Answer 51

1. less ethical issues as no embryos involved 2. no immune response as own stem cells used 3. anything can be replaces In theory

Question 52

What is a disadvantage of Induced Pluripotent stem cells?

Answer 52

1. could lead to cancer | 2. More research needs to be done on pathways

Question 53

What is Apotosis

Answer 53

programmed cell death

Question 54

How is apoptosis stimulated?

Answer 54

by a signalling process which activate intracellular suicide proteases

Question 55

What are the 3 steps in apoptosis?

Answer 55

1. structure breaks down 2. Cytoskelton collapses 3. mini cells are created and engulfed by phagocytosis

Question 56

What is necrosis?

Answer 56

Cell lysis / bursting

Question 57

Wha the 3 steps to necrosis?

Answer 57

1. cell membrane is destroyed 2. cell content is released 3. phagocytosis and enzymes degrade further

Question 58

What can apoptosis be used to tackle?

Answer 58

cancer