Topic 2A: Cell structure and division

?
What are organelles?
They're parts of cells that have a specific function
1 of 94
What organisms are eukaryotic?
Animals, plants, algi and fungi
2 of 94
What extra parts do plant cells have that animal cells do not?
Plant cells have a cellulose cell wall, a vacuole and chloroplasts
3 of 94
Are starch grains organelles?
NO
4 of 94
What is the difference (in terms of chloroplasts) of algal and plant cells?
Algal cells have chloroplasts in a different shape and size for example, they may just have one big chloroplast instead of several smaller ones (like a plant cell)
5 of 94
What's the difference between fungal and plant cells?
Fungal cells' cell wall is made of chitin, not cellulose and they don't have chloroplasts
6 of 94
What is the function of the cell-surface membrane?
They regulare the movement of substances in and out of the cell. They also have receptor molecules to allow the cell respond to hormones
7 of 94
What is the cell-surface membrane made from?
Mainly lipids and proteins
8 of 94
What is the function of the nucleus?
It controls the cell's activities by controlling the transcription of DNA
9 of 94
What does the nucleolus make?
Ribosomes
10 of 94
What is the function of the mitochondria?
It is the site of aerobic respiration and it produces ATP
11 of 94
Name the 4 parts of mitochondria
Matrix, crista, inner/outer membrane
12 of 94
What is the function of the chloroplasts?
They're the site of photosynthesis
13 of 94
What are grana linked together by?
Lamellae
14 of 94
What is the stroma?
It is a thick liquid found in the chloroplasts
15 of 94
What is the function of the golgi apparatus?
They process and package new lipids and proteins and make lysosomes
16 of 94
What is the golgi apparatus?
They're a group of fluid-filled membrane bound sacs
17 of 94
What is the function of the golgi vesicle?
They store lipids and proteins made by the apparatus and transports them out of the cell
18 of 94
What is the function of lysosomes?
They contain digestive enzymes called lysozymes that can digest invading cells or break down worn out components of the cell
19 of 94
What is the function of ribosomes?
Where proteins are made (translation)
20 of 94
Where can you find a ribosome in the cell?
Free floating in the cytoplasm or attatched to the rough endoplasmic reticulum
21 of 94
What is the function of the rough endoplasmic reticulum?
It folds and processes proteins that have been made at the ribosomes
22 of 94
What is the function of the smooth endoplasmic reticulum?
They synthesise and process lipids
23 of 94
What's different about the structure of the RER compared to SER?
RER is covered in ribosomes, SER is not
24 of 94
What's the function of the cell wall?
Supports the cell and prevents it from changing shape
25 of 94
In what cells is a cell wall found?
Plant, algae and fungi cells
26 of 94
What is a tonoplast?
The surrounding membrane of the cell vacuole
27 of 94
What is the function of the cell vacuole?
To maintain pressure inside the cell and keep it rigid - this stops the plant wilting. It also isolates the unwanted chemicals inside the cell
28 of 94
What is the cell sap made of?
It is a weak solution of sugar and salts
29 of 94
How are sperm cells adapted to their function?
They contain a lot of mitochondria to provide a lot of energy as they swim 2 the egg
30 of 94
How are red blood cells adapted to their function?
They have no nucleus to make room for haemoglobin
31 of 94
How are epithelial cells adapted to their function?
Microvilli & villi to increase surface area, they have lots of mitochondria for active transport
32 of 94
What is an organ?
Different tissues that work together to perform a particular function
33 of 94
What are tissues?
A collection of specialised cells that are grouped together that work together to perform a particular function
34 of 94
Are ribosomes bigger or smaller in a prokaryotic cell compared to a eukaryotic cell?
They're smaller in a prokaryotic cell
35 of 94
What is a cell wall made out of in a prokaryotic cell?
Murein (a glycoprotein)
36 of 94
What is the point of having a capsule made of secreted slime?
It helps protect bacteria from the attack by cells of the immune system
37 of 94
What does a prokaryotic cell have instead of a nucelus?
It has free floating DNA which is circuar and one long coiled up strand. Also has plasmids
38 of 94
What is the function of a flagellum?
It helps the cell move
39 of 94
What do the genes in plasmids contain?
The genes contain things like antibiotic resistance
40 of 94
How big are prokaryotic cells?
2 micrometres in diameter (0.002mm)
41 of 94
What's bigger: eukaryotic or prokaryotic cells?
Eukaryotic cells: 0.1mm compared to 0.002mm
42 of 94
What is the process by which prokaryotic cells replicate
Binary fission
43 of 94
What happens during binary fission?
The prokaryotic cell replicates its genetic material before physically splitting into two daughter cells
44 of 94
What are host cells?
The cells that viruses invade and reproduce inside of
45 of 94
What are the 3 parts of a virus?
Core of genetic material, capsid and attatchment proteins
46 of 94
What is a capsid?
A protein coat with attatchment proteins sticking out of it
47 of 94
What do attatchment proteins cling on to?
The suitable host cell's complementary receptor proteins on the cell membrane
48 of 94
Do viruses have DNA or RNA?
They can have either
49 of 94
What is magnification?
How much bigger he image is than the specimen
50 of 94
How is magnification calculated?
Magnification = size of image / size of real object
51 of 94
Order these from smallest to biggest: um nm mm
nm um mm
52 of 94
What is resolution?
How detailed the image is - how well a microscope distinguishes between two points that are close together
53 of 94
How do you convert mm into um?
x1000
54 of 94
What are the two types of microscopes?
Optical and electron
55 of 94
What are the two types of electron microscope?
Transmission and scanning
56 of 94
How does a TEM work?
They use electromagnets to focus a beam of electrons which is then transmitted through the specimen - denser parts absorb more electrons which makes it look darker
57 of 94
How does a SEM work?
SEMs scan a beam of electrons across the specimen which knocks off electrons from it which are then gathered in a cathode ray tube to form an image
58 of 94
What's an advantage of TEMs?
They give high resolution images, so show small objects
59 of 94
What are the disadvantages of TEMs?
They can only be used on thin and non living specimens
60 of 94
What are the advantages of SEMs?
They can be used on thick specimens & can be 3D
61 of 94
What are the disadvantages of SEMs?
They give lower resolution images than TEMs and can only be used on non living specimens
62 of 94
Why are TEMs not good for looking at living organisms?
They have to be viewed in a vacuum
63 of 94
Is the magnification higher in a optical or electron microscope?
Electron (1 x 500,000) (vs optical: 1 x 1,500)
64 of 94
Is the resolution higher in a optical or electron microscope?
Electron (max of 0.0002um) (vs optical max of 0.2um)
65 of 94
Why are stains used?
They're used to highlight objects in a cell
66 of 94
What are microscope artefacts?
They are things you can see down the microscope that aren't part of the cell or specimen you're looking at (e.g. air bubbles or dust)
67 of 94
What are some examples of microscope artefacts?
Air bubbles, fingerprints, dust
68 of 94
Why do microscope artefacts appear?
Due to inaccuracies caused by squashing and staining the sample
69 of 94
What's the process that seperates organelles in a cell?
Cell fractionation
70 of 94
What are the three steps to cell fractionation?
1. Homogenisation 2. Filtration 3. Ultracentrifugation
71 of 94
Give two says homogenisation can be done
Vibrating the cells or grinding them in a blender
72 of 94
Why should the solution be isotonic during homogenisation?
To prevent damage to the organelles through osmosis
73 of 94
What does isotonic mean?
The same concentration of chemicals as the cells in the solution (or something idk)
74 of 94
Why is a buffer solution added during homogenisation?
To maintain pH
75 of 94
In what order are the organelles seperated during ultracentrifugation?
Nuclei, Chloroplasts, Mitochondria, Lysosomes, ER, Ribosomes
76 of 94
What is a centrifuge?
A machine that seperates material by spinning
77 of 94
Where are the heavier organelles found during ultracentrifugation?
In the pellet
78 of 94
What are the 3 stages of interphase?
G1, synthesis and G2
79 of 94
What happens during G1?
Cells grow new organelles and proteins are made
80 of 94
What happens during synthesis?
The cell replicates its DNA, ready to divide by mitosis
81 of 94
What happens during G2?
The cell keeps growing and proteins needed for cell division are made
82 of 94
BRIEFLY describe what happens during mitosis
A parent cell divides to produce two genetically identical daughter cells
83 of 94
What are the 5 stages of mitosis?
Interphase, prophase, metaphase, anaphase, telophase (IPMAT init)
84 of 94
What is a centromere?
What joins two chromosomes in the middle
85 of 94
What is a chromatid?
One arm of a double stranded chromosome
86 of 94
What happens during prophase?
Chromosomes condense, centrioles move to opposite ends of the cell, the nuclear envelope breaks down and chromosomes lie free in the cytoplasm
87 of 94
What happens during metaphase?
The chromosomes line up along the middle of the cell and become attatched to the spindle by their centromere
88 of 94
What happens during anaphase?
The centromeres divide and spindles contract, pulling chromatids to opposite poles of the spindle.
89 of 94
What happens during telophase?
The chromatids reach opposite poles on the spindle and they uncoil to just be chromosomes again. A nuclear envelope forms and cytokenisis happens
90 of 94
What is cytokenisis?
Bascially when the cytoplasm divides
91 of 94
What is cancer?
It is a tumour that invades surrounding tissue
92 of 94
What causes cancer?
A mutation in a gene that controls cell division, so cells divide uncontrollably
93 of 94
How do you calculate mitotic index?
Mitotic index = number of cells with visible chromosomes / total number of cells observed
94 of 94

Other cards in this set

Card 2

Front

What organisms are eukaryotic?

Back

Animals, plants, algi and fungi

Card 3

Front

What extra parts do plant cells have that animal cells do not?

Back

Preview of the front of card 3

Card 4

Front

Are starch grains organelles?

Back

Preview of the front of card 4

Card 5

Front

What is the difference (in terms of chloroplasts) of algal and plant cells?

Back

Preview of the front of card 5
View more cards

Comments

Workangel_24

Report

Great flash cards!!!

Similar Biology resources:

See all Biology resources »See all Cellular processes and structure resources »