Cell structure - Organelles Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

describe the structure of the nucleus

A

nucleoplasm contains chromatin (DNA + protein)
nuclear envelope
nuclear pores
nucleolus
outer membrane is continuous with rough ER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

describe the function of the nucleoplasm

A

contains DNA that codes for proteins
during cell division chromatin condenses into chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

describe the function of the nuclear envelope

A

double membrane that encloses DNA and keeps it separate from reactions in the cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

describe the function of the nuclear pores

A

allow entry of molecules for DNA replication
exit of mRNA for protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

describe the function of the nucleolus

A

manufactures ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

why is the outer membrane being continuous with the rough ER useful

A

allows easy transport of substances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

describe the structure of the endoplasmic reticulum

A

cisternae: membrane bound sacs
rough ER: covered with ribosomes
smooth ER: lacks ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

describe the function of the cisternae in ER

A

allow transport within the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

describe the function of the rough ER

A

synthesise and transport proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

describe the function of the smooth ER

A

synthesis and transport lipids and steroids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

describe the structure of the ribosomes

A

2 subunits made of rRNA and protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

where are ribosomes synthesised and how do they leave

A

synthesised in nucleolus and then pass through the nuclear pores to the cytoplasm or rough ER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the two types of ribosomes

A

22nm/80S(eukaryotic cells)
18nm/70S (prokaryotic cells, chloroplasts, mitochondria)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

describe the function of ribosomes

A

protein synthesis
binds to and moves along the mRNA and translates it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

describe the structure of the Golgi apparatus

A

a stack of flattened membrane bound cavities called cisternae
secretory vesicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

describe the function of cisternae in Golgi apparatus

A

modifies proteins (e.g adds carbohydrates)
packages proteins into secretory vesicles or lysosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

describe the function of the secretory vesicles

A

produced by Golgi apparatus, will fuse with the cell surface membrane to release hormones or enzymes from the cell (exocytosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

describe the structure of the lysosomes

A

vesicles which contain hydrolytic enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

describe the function of the lysosomes

A

isolate potentially harmful enzymes from the cell
break down material ingested by phagocytes
break down old organelles
break down cells when they die

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

describe the structure of the mitochondria

A

double membrane
inner membrane folded to form cristae
matrix contains: small ribosomes (18nm/70S), circular DNA, enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

where are large numbers of mitochondria found

A

cells requiring lots of energy e.g muscle and liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

describe the function of the double membrane in mitochondria

A

isolates reactions in aerobic respiration (ATP production)

23
Q

describe the function of the inner membrane folded to form cristae

A

increases surface area for enzymes to be attached

24
Q

describe the function of the small ribosomes in the matrix

A

protein synthesis

25
Q

describe the function of the circular DNA in the matrix

A

codes for proteins

26
Q

describe the function of the enzymes in the matrix

A

for aerobic respiration

27
Q

describe the structure of the chloroplasts

A

double membrane
membrane-bound sacs called thylakoids stacked into grana
stroma containing:
enzymes, starch grains, small ribosomes, DNA, lipid droplets

28
Q

describe the function of the double membrane in the chloroplast

A

isolates photosynthesis reactions

29
Q

describe the function of the thylakoids stacked into grana

A

increases surface area for chlorophyll molecules to be attached

30
Q

describe the function of the enzymes in the stroma

A

for photosynthetic reactions

31
Q

describe the function of the starch grains in the stroma

A

carbohydrate store

32
Q

describe the function of the small ribosomes in the stroma

A

proteins synthesis

33
Q

describe the function of the DNA in the stroma

A

codes for proteins

34
Q

describe the function of the lipid droplets in the stroma

A

for membranes

35
Q

give examples of cells containing chloroplasts

A

palisade, spongy cell, guard cell

36
Q

describe the structure of centrioles

A

2 centrioles found in all animal cells at right angles to each other, adjacent to the nucleus
composed of 9 sets of 3 microtubules

37
Q

where are the centrioles found

A

algae, animal cells, fungi but NOT plants

38
Q

describe the function of centrioles

A

form the spindle fibres during nuclear division to control the separation of chromatids and chromosomes

39
Q

which organelle is not membrane bound

A

ribosome

40
Q

describe the structure of the cytoskeleton

A

composed of microtubules (fine hollow tubes), microfilaments (small solid protein strands), intermediate filaments (more stable protein strands) (mechanical strength)

41
Q

describe the function of the cytoskeleton

A

support cell organelles position
enable movement of organelles e.g vesicles and proteins, RNA (uses ATP)
strengthen cell and maintains shape
allows cell movement e.g phagocytes
allows cell to change shape

42
Q

what are other structures containing microtubules

A

spindle fibres - separate chromosomes
cilia and flagella - movement

43
Q

describe the structure of the cilia and flagella

A

composed of two central microtubules surrounded by 9 pairs
many short threadlike projections = cilia
long whip-like projection = flagellum (prokaryotes), undulipodium (eukaryotes e.g sperm)

44
Q

describe the function of microtubules in cilia and flagella

A

sliding of microtubules brings about movement. this uses ATP

45
Q

describe the function of the cilia

A

cilia in bronchi and trachea waft mucus towards throat
cilia in oviduct waft the ovum towards the uterus

46
Q

describe the function of the flagella and undulipodium

A

mainly used for movement

47
Q

describe the structure of the vacuole

A

cell sap contained within the tonoplast (vacuolar membrane)

48
Q

describe the function of the vacuole

A

maintains turgor for support
storage e.g dissolved sugars, mineral ions, pigments, enzymes, amino acids, waste substances (such as tannins)

49
Q

describe the structure of the cell wall

A

made of cellulose secreted by the living cell
rigid and permeable
can be modified by lignin
can contain pores which are penetrated by plasmodesmata
middle lamella (contains pectin)

50
Q

describe the vacuole in plants compared to animals

A

common, large and permanent in plant cells
absent or small and temporary in animal cells

51
Q

describe the function of the cell wall

A

support and protection
allows cells to become turgid which aids in support
prevents osmotic bursting of the cell

52
Q

describe the function of the pores in the cell wall

A

links neighbouring cells

53
Q

describe the function of the middle lamella

A

cements neighbouring cells together

54
Q

how does the cytoskeleton move organelles around the cell

A

using microtubules