Topic 2A: Cell Structure and Division Flashcards

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

Describe a lysosome

A

A round organelle surrounded by a membrane, type of golgi vesicle

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

What’s the function of a lysosome?

A

Contains digestive enzymes (lysozymes), used to digest invading cells or to break down worn out components

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

Describe a ribosome

A

A very small organelle that floats free in the cytoplasm or attached to rough ER, made of proteins/RNA

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

What’s the function of ribosomes?

A

Where proteins are made-protein synthesis

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

Describe rough ER

A

A system of membranes enclosing a fluid-filled space, covered in ribosomes

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

What’s the function of rough ER?

A

Folds and processes proteins that have been made in the ribosomes

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

Describe smooth ER

A

A system of membranes like RER, but without ribosomes

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

What’s the function of smooth ER?

A

Synthesis’s and processes lipids

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

Describe cell walls

A

A rigid structure surrounding cells in plants, algae and fungi mainly made of the carbs and cellulose

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

What’s the function of cell walls?

A

Supports cells and prevents them from changing shape

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

Describe the vacuole

A

Membrane-bound organelle found in the cytoplasm, contains cell sap (surrounding membrane is tonoplast)

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

What’s the function of the vacuole?

A

Helps maintain pressure inside the cells and keep it rigid (stops plant wilting)

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

How do Prokaryotic cells replicate?

A

Binary Fission

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

Explain binary fission

A

Step 1) Circular DNA replicates main DNA once, plasmids divide multiple times
Step 2) Cells get bigger the DNA loops move to opposite poles.
Step 3) Cytoplasm divides
Step 4) 2 daughter cells are produced, each cell has one circular DNA but multiple plasmids

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

Viruses aren’t cells, what are they?

A

Acellular, nucleic acids surrounding by a protein coat

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

What do viruses need to re-produce?

A

Host-cell

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

Once the virus is attached to the host-cell what does it do?

A

Inject their DNA/RNA into the host cell

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

What’s the magnification equation?

A

Magnification= size of image/real object size

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

How do you get from micrometers to nanometers?

A

X1000

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

How do you get from nanometers to micrometers?

A

/1000

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

What are microscope artifacts?

A

Things you see down a microscope that aren’t part of the cell, e.g fingerprints/bubbles

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

What’s a TEM microscope?

A

TEM use electromagnets to focus a beam of electrons this is transmitted through the specimen. Denser parts of the specimen absorb more electrons appearing darker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What’s a SEM microscope?

A

SEM’s scan a beam of electrons across a specimen. Knocking off electrons from the specimen (3D)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Describe the chloroplast

A

Small flattened structure found in plant cells and algal cells, double membrane, inside also thylakoid membranes, forming grana

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What’s the function of chloroplast?

A

Where photosynthesis occurs

26
Q

Describe the Golgi apparatus

A

A group of fluid-filled membrane-bound flattened sacs, vesicles are often seen at the edges

27
Q

What’s the function of Golgi apparatus.

A

It processes and packages new lipids and proteins, also making lysosomes

28
Q

Describe golgi vesicles

A

A small fluid filled sac in the cytoplasm, surrounded by a membrane

29
Q

What’s the function of Golgi vesicles?

A

Stores lipids and proteins made by the Golgi apparatus and transports them out of the cell

30
Q

What is magnification?

A

How much bigger the image is than the original

31
Q

What is resolution?

A

Resolution is how detailed the image is, how well the microscope distinguishes between 2 points

32
Q

Name 2 types of microscope

A

Optical (light) microscopes and electron microscopes

33
Q

Name the 2 types of electron microscopes

A

Transmission and scanning (TEM&SEM)

34
Q

What do optical microscopes do?

A

Use light to form an image

35
Q

What’s the max resolution of optical microscopes?

A

0.2um including ribosomes ER and lysosomes

36
Q

What’s the max magnification of optical microscope?

A

1500x

37
Q

What do electron microscopes do?

A

Use electrons to form an image

38
Q

What’s the max resolution of a electron microscopes?

A

0.0002um

39
Q

What’s the max magnification of an electron microscope?

A

1500000x

40
Q

What are epithelial cells specialized to do?

A

Adapted to absorb food efficiently

41
Q

How are epithelial cells specialized?

A

Have villi for increased SA, micro villi for increased SA and loads of mitochondria for lots of energy

42
Q

How are red blood cells specialized?

A

No nucleus to make room for oxygen carrying haemoglobin

43
Q

How are sperm cells specialized?

A

Lots of mitochondria providing large amounts of energy

44
Q

What’s a tissue?

A

A group of cells grouped together to form tissues (Tissue-organ-organ system)

45
Q

What type of organisms is a prokaryotic cell?

A

Single celled

46
Q

What does the flagellum do?

A

Used for locomotion

47
Q

What are plasmids?

A

Small loops of DNA, small loops aren’t part of the main circular DNA, for antibiotic resistance

48
Q

What does the capsule do?

A

Capsule made up of secreted slime, protecting the bacteria from attacking other cells (immune system)

49
Q

What is the cell wall in fungal cells made out of vs plant cells?

A

Fungal= chitin Plant= cellulose

50
Q

Describe the cell-surface membrane

A

Membrane found on the surface of animal cells and just inside the cell wall of other cells, mainly made from lipids and proteins

51
Q

What’s the function of the cell-surface membrane?

A

Regulates the movement of substances into and out of the cell
Also, has receptors on it that can respond to chemicals like hormones

52
Q

Describe the nucleus

A

An organelle surrounded by a nuclear membrane (double membrane) nucleus contains chromosomes and nucleolus

53
Q

What’s the function of the nucleus?

A

Controls the cell activities contains instructions to make proteins and ribosomes

54
Q

Describe mitochondria

A

Oval-shaped, double membrane (inner folded unto cristae) inside is the matrix, containing enzymes for respiration

55
Q

What’s the function of mitochondria?

A

Site of aerobic respiration, producing ATP

56
Q

Name an advantage and disadvantage of SEMS microscopes?

A

Ad: can be used on thick specimens and can be 3D
Dis: Gives lower resolution than TEMS, only used on non-living specimens

57
Q

Name an advantage and disadvantage of TEMS microscopes?

A

Ad: Give high resolution, show small objects
Dis: Can only be used on non-lining and thin specimens

58
Q

What’s cell fractionation?

A

Separating organelles from the rest of the cell

59
Q

What does homogenisation do and how do you do it?

A

Breaking up the cells, by vibrating or grinding the cells this breaks up the plasma membranes
Solution must be kept ice-cold, isotonic and a buffer solution added to maintain pH

60
Q

Why do we filter the solution?

A

To get rid of larger cell debris

61
Q

What does ultracentrifugation do and why?

A

Separating the organelles, poured into tube and put into a centrifuge spun on a low speed. Heavy organelles are spun off first, when you increase speed each time lighter organelles come of each time

62
Q

What organelles are spun off, in which order?

A

Nuclei, mitochondria, lysosomes, ER and ribosomes