Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology > cells > Flashcards

cells Flashcards

(55 cards)

Start Studying
1
Q

What organelles are present in prokaryotic cells but not eukaryotic cells?

A

flagellum, DNA loop, centrioles, plasmids

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

What is the function of the cell surface membrane?

A

controls what enters and leaves the cell.

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

What is the function of the nucleus?

A

controls protein synthesis by mRNA and tRNA. Manufactures RNA and ribosomes.

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

What is the function of the mitochondrion?

A

Site of aerobic respiration - production of ATP cells with high levels of metabolic activity.

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

What is the function of chloroplast?

A

Site of photosynthesis.

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

What is the function of golgi apparatus?

A

Add carbohydrates to proteins, produce secretary enzymes, secrete carbohydrates, transport modify and store lipids, form lysosomes.

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

What is the function of lysosomes ?

A

Isolation of enzymes before release to outside of the cell, hydrolyse material ingested by phagocytic cells, release enzymes to destroy material around cell.

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

What is the function of ribosomes?

A

protein synthesis

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

What is the function of rough endoplasmic reticulum?

A

protein synthesis

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

What is the function of smooth endoplasmic reticulum?

A

synthesis and store of lipids and carbohydrates.

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

What is the function of the cell wall?

A

mechanical strength to prevent bursting from osmotic pressure, allow water to pass along it.

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

What is the function of the cell vacuole?

A

support herbaceous parts of woody plants by making cells turgid, contains sugars and amino acids that may act as a temporary food store.

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

What is differentiation?

A

The process by which cells become specialised for different functions.

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

Define tissue.

A

A group of similar cells which carry out a specific function.

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

What are the advantages of a light microscope?

A

real colours, can use a living sample

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

What are the disadvantages of a light microscope?

A

lower resolution, can not see smaller organelles, lower magnification.

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

what are the advantages of scanning electron microscope?

A

3D image, thick specimens, false colour

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

What are the disadvantages of the scanning electron impact microscope?

A

Sample must be in a vacuum, cant view living samples, lower resolution than T.E.M

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

What are the advantages of a transmission electron microscope?

A

higher resolution so can see ultrastructure

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

What are the disadvantages of the transmission electron microscope?

A

very thin specimen, black & white image, need a vacuum, image contains artefacts, 2D image.

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

What is the equation for magnification?

A

image size = actual size x magnification

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

Explain how you would prepare a stained temporary mount.

A

1) use a knife to cut a thin slice of the specimen
2) use forceps to place the specimen on the slide.
3) add iodine
4) use a mounted needle to lower the cover slip onto the slide.

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

What is cell fractionation used for?

Study These Flashcards
A

Separating different organelles of a cell so they can be studied in detail.

24
Q

What is the first stage of cell fractionation?

Study These Flashcards
A

Tissue is cut up and kept in a cold, isotonic buffered solution.

25
What is the second stage of cell fractionation?
cut-up tissue is further broken up in homogeniser and filtered to remove large cell debris.
26
What is the third stage of cell fractionation?
Homogenised tissue is spun in an ultracentrifuge at a low speed for 10 minutes to force the heaviest organelles to the bottom.
27
What is the fourth stage of cell fractionation?
The supernatent is transferred to another tube and spun at a higher speed. repeated at different speeds,
28
Order the organelles in order of least to most dense.
ribosomes, endoplasmic reticulum, mitochondria, nucleus
29
Where is murein used in prokaryotic cells?
cell wall
30
What occurs in interphase?
cell prepares for division
31
What happens during prophase?
chromosomes condense to get fatter and smaller. centrioles move to opposite ends of the cell.
32
What happens during metaphase?
spindle apparatus forms in the cytoplasm, chromosomes align at the centre.
33
What happens during anaphase?
Spindle fibres attach to chromatids to pull them to each side.
34
What happens during telophase?
Nuclear envelope and nucleus forms
35
How do you calculate mitotic index?
number of cells with visible chromosomes/ total number of cells observed
36
How does a tumour cell develop?
early tumour starts enlarging developing blood vessels and lymphatic vessels. tumour cells squeeze into blood vessels. tumour cells travel in blood and then stick to blood vessels wall.
37
Define magnification
How many times larger the image is compared to the object
38
Define resolution
Minimum distance between two objects where they can still be viewed as separate
39
How do prokaryotic cells divide?
Binary fission
40
What happens during binary fission?
1) Circular DNA molecule replicates and both copies attach to cell membrane. 2) Plasmids replicates 3) Cell membrane begins to grow between the two DNA molecules and begins to pinch inwards dividing cytoplasm into two. 4) a new cell wall forms between the two molecules of DNA, dividing the original cell into 2 identical daughter cells, each with a single copy of the circular DNA.
41
Why is the cell membrane described as fluid-mosaic?
Individual phospholipids molecules can move relative to one another giving the membrane a flexible shape. However also mosaic as phospholipids and individual proteins are embedded in the membrane which vary in shape and size.
42
What is the function of fatty acids in the cell membrane?
Lipids soluble substances can enter. Prevent water soluble substances entering/leaving. Membrane flexible & self healing
43
What is the function of extrinsic/intrinsic proteins in the cell membrane?
Act as channels transporting water soluble substances. Allow active transport Cell surface receptors Help cells adhere
44
What is the function of cholesterol in the cell membrane?
Reduce lateral movement Make membranes less fluid at high temperatures
45
What is the function of glycolipids in the cell membrane?
Recognition site Cells attach to form tissues
46
What is the function of glycoproteins in the cell membrane?
Recognition site Allow cells to recognize
47
What is the function of the cell membrane?
Separate organelles for specific metabolic reactions. Provide internal support. Isolate enzymes that might damage the cell.
48
What sort of molecules are transferred in simple diffusion?
Lipid soluble, very small molecules
49
What sort of molecules are transported in facilitated diffusion?
Water & soluble ions Specific ions
50
What is the difference between facilitated and simple diffusion?
Simple diffusion the cell cannot control the movement as it depends on the conc gradient. In facilitated diffusion the carrier protein can open and close the channel proteins to allow diffusion.
51
Define osmosis.
The passage of water from a region of high water potential to a region of lower water potential through a partially permeable membrane.
52
What are aquaporins?
Integral membrane proteins that serve as channels in transfer of water.
53
How is the small intestine adapted for efficient diffusion?
Many channels and carrier proteins in the lining of small intestine. Large surface are from microvilli Short diffusion distance, one cell thick Good blood supply so high concentration gradient
54
Describe active transport.
Molecules bind to a complimentary receptor on the carrier protein. ATP binds to carrier protein and is hydrolysed into ADP and a phosphate. Causes carrier protein to change shape and release molecule on other side. Phosphate ion is released and protein returns to original shape.
55
Describe the process of co-transport.
1)Sodium ions are actively transported out of epithelial cell into blood. (Reducess concentration of sodium in epithelial cell) 2)Sodium ions diffuse via facilitated diffusion from the illeum into epitheliaal cell to maintain conc gradient. 3) sodium ion has to attach to co-transporter protein so when it binds to a complimentary receptor it allows glucose to bind too. 4) glucose moves by facilitated diffusion into blood from epithelial cell

Biology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions