Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GCSE Biology OCR A > B1 > Flashcards

B1 Flashcards

You may prefer our related Brainscape-certified flashcards:
GCSE Religious Studies - Edexcel Route A flashcards GCSE Religious Studies - Eduqas Route A flashcards AP® Biology flashcards GCSE Geography - AQA flashcards Biology 101 flashcards GCSE Religious Studies - Edexcel Route B flashcards GCSE Religious Studies - Eduqas Route B flashcards
1
Q

What are Eukaryotic cells?

A

Cells that contain genetic material in a nucleus
Animal and plant cells
Larger (10 - 100 micrometers)

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

What are prokaryotic cells?

A

Genetic material floats in cytoplasm (no nucleus)
Bacteria
Smaller ( 1-10 micrometers)

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

What is the function of a nucleus?

A

▫️To contain genetic material - which codes for a particular protein ( arranged in chromosomes )
▫️to control cell activity
▫️

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

What is the function of the mitochondria?

A

▫️ contains enzymes for the site of respiration (aerobic)

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

What is the function of the cell membrane?

A

▫️contains receptor molecules for selective control of what enters and exits the cell

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

What is the function of cytoplasm?

A

▫️substance in which chemical reactions occur
▫️contains enzymes

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

What is the function of vacuole?

A

▫️keeps the cell rigid and upright
▫️contains cell sap

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

What is the function of Ribosomes?

A

▫️Site of protein synthesis

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

What is the function of chloroplast?

A

▫️site for photosynthesis
▫️contains chlorophyll 🟩 which transfers energy from the sun as light for photosynthesis

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

What is the function of the cell wall?

A

▫️Provides strength to the cell
▫️made of cellulose

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

Name some examples of prokaryotes:

A

Aka bacteria
🦠salmonella
🦠clostridium botrildum
🦠E- coli
🦠staphylococcus

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

What is the cell wall made out of in a prokaryote ?

A

Peptidoglycan

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

Describe prokaryotic genetic material?

A

▫️floating freely in the cytoplasm
▫️singular circular (chromosome )
♾
▫️controls cell activities

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

What are the functions of plasmids?

A

▫️small loops of extra DNA
▫️normally for things like drug resistance not essential

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

Why is the function of flagellum?

A

▫️Tails that allow the cell to move through liquids

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

What is the function of pilli?

A

▫️small hairs to attach to structures and transfer genetic material

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

What is the function of slime capsules?

A

▫️outmost layer
▫️protect from drying out
▫️helps cells to stick to smooth surfaces

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

Eyepiece lens

A

🔹at the very top
🔹used to see image

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

Objective lens

A

🔹normally three of them
🔹used to magnify the image

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

How do you observe cells through a microscope

A

🔹lower stage
🔹use Objective lens with lowest magnification
🔷first placed onto a slide, sometimes stained
🔹slip placed on top
🔹mounted onto the stage
🔹raise the stage to it’s highest position
🔹turn fine focus knob

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

What is the difference between fine focus and corse focus?

A

Corse focus lifts the stage
Fine focus adjusts the amount of light

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

How does a light microscope work?

A

Light shone onto object placed on stage .
Then through objective and eyepiece lens

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

What is total magnification?

A

Total magnification = objective lens magnification ✖️eyepiece lens

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

What is the magnification of an object

A

I A M
Image size = actual size ✖️magnification

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

Why stain cells ?

A

🔹as some cells are colourless, easier to observe
🔹to highlight sub cellular structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is resolution?

A

The ability to distinguish between two points that are close to each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is magnification?

A

The degree to which the size of an image is larger than the real object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Transmission electron microscope (TEM)

A

🔹has a very high magnification
🔹work like a light microscope but pass electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Scanning electron microscope (SEM)

A

🔹produces 3D images

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are advantages of light microscopes?

A

🔹cheap
🔹easily transportable
🔹can look at living specimens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are disadvantages of light microscopes?

A

🔹low resolution ( limited by the wavelength of visible light)
🔹low magnification
🔹staining required to see one specimens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are disadvantages of an electron microscope?

A

🔹cannot see living things as needs to be placed in a vacuum
🔹very expensive
🔹not so transportable
🔹requires special skills/ training

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What does DNA stand for ?

A

Deoxyribonucleic acid 🧬

34
Q

How many chromosomes are in people?

A

46
23 pairs
Xxxxxxx

35
Q

What does a chromosome consist of ?

A

🔺long strands of DNA combined with protein

36
Q

Describe the structure of a DNA strand:

A

🔺a polymer made up of nucleotides (monomers)
🔺double helix
🔺anti parallel (2 strands ) joined by bases

37
Q

What does a nucleotide consist of

A

Phosphate
Sugar
Base
🟢
/
🟦—-▪️

38
Q

What are the four bases?

A

🟦adenine
🟪cytosine
🟥guanine
🟧thymine

39
Q

What is complementary bases bonding

A

Base pairs always bonding together in the same formation
🟦 A = T 🟥
🟪 C = G 🟧

40
Q

What is a gene?

A

A short length of the DNA molecule .
Each gene codes for a specific sequence of amino acids which make a specific protein

41
Q

What is transcription?

A

🟢DNA too big to leave the nucleus
🟢DNA unzips around the gene and complementary base pairs attach forming a sugar phosphate backbone forming m RNA
🟢mRNA detaches and DNA zips back up
🟢goes from nucleus to ribosome

42
Q

What is translation?

A

🟢mRNA goes to a ribosome
🟢ribosome reads mRNA ‘s nucleotides in codons(3)
🟢each anti codon reads a specific amino acid brought by tRNA
🟢the amino acids form a chain from peptide bonding creating protein

43
Q

What is the complementary base bonding of mRNA?

A

No thymine , instead uracil
🟪c = g 🟧
⬛️ u = a🟥

44
Q

What are some differences between mRNA and DNA

A

🟢mRNA is a single strand
🟢DNA is much bigger
🟢mRNA can leave the nucleus
🟢mRNA uses uracil instead if thymine

45
Q

What are enzymes?

A

🟤Biological catalyst: sped up reactions without being used up themselves.
🟤Essential for metabolism
🟤Made from proteins
🟤reusable

46
Q

What do enzymes do to molecules ?

A

🟤build larger molecules from small ones
🟤break down large molecules into smaller ones

47
Q

What is an active site?

A

🟤Place where substrate binds to enzyme .
🟤To form an enzyme substrate complex where the reaction takes place bad products are released from surface of the enzyme.

48
Q

How does temperature and pH affect enzymes?

A

Optimum temp = 37°c
Optimum pH = 7
Increases till Ot and then decrease as enzyme denatures
📈📉

49
Q

What does denaturing mean?

A

When the active site of an enzyme changes.
Enzyme substrate complex cannot form
Rate of reaction decreases

50
Q

How does enzyme concentration affect enzymes?

A

It increase the reaction until there are no more substrates, this suddenly stops the reaction because there are not enough substrate molecules to react with the enzymes

   /|
/   |   /     |  /       |
51
Q

Why do cells need energy?

A
  1. Movement
  2. Thermoregulation
  3. Biosynthesis eg: protein synthesis
    * building larger molecules from smaller molecules
52
Q

What is cellular respiration

A

🟠an exothermic reaction
🟠transfers energy from glucose
🟠is always happening
🟠supplies ATP to all living organisms

53
Q

What is metabolism?

A

As the chemical processes that occur within a living organism to maintain life

54
Q

Aerobic respiration

A

🟠most efficient way of transferring energy
🟠used when there is enough oxygen
🟠happens in plants and animals and bacteria
🟠occurs in mitochondria

55
Q

What is the word equation of aerobic respiration?

A

Oxygen + glucose —> carbon dioxide + water + (ATP)
Chemical has a six before everything apart from glucose

56
Q

What is anaerobic respiration in animals?

A

🟠Glucose —> lactic acid
🟠When not enough oxygen
🟠takes place in the cytoplasm

57
Q

Why is anaerobic respiration not preferred?

A

🟠incomplete breakdown of glucose
🟠lactic acid build up
🟠doesn’t yield as much energy

58
Q

What is anaerobic respiration in plants & yeast ?

A

Glucose—> ethanol + carbon dioxide
In yeast it called fermentation , carbon dioxide can be used in baking and ethanol makes alcohol

59
Q

How are carbohydrates broken down?

A

🔻enzymes called carbohydrase eg: Amylase
🔻break the carbohydrates into simple sugars
Carbohydrate = substrate

60
Q

How are proteins broken down?

A

🔻broken down by protease enzymes
🔻turn into amino acids

61
Q

How are lipids broken down?

A

🔻broken down by lipase
🔻into 1 glycerol and 3 fatty acids released into the blood stream

62
Q

What is photosynthesis?

A

🟡making glucose from sunlight
🟡endothermic reaction
🟡occurs in the chlorophyll
🟡 carbon dioxide + water —> glucose + oxygen

63
Q

Where do the reactants for photosynthesis come from?

A

🟡carbon dioxide diffuses from the stomata
🟡water comes via osmosis in the roots from the soil up the xylem

64
Q

What is the light dependent phase in photosynthesis?

A

🟡light splitting the water into hydrogen and oxygen

65
Q

What is the light independent phase of photosynthesis?

A

🟡 the carbon dioxide being add to the hydrogen to form glucose

66
Q

How does the plant use glucose?

A

🟡used for respiration
🟡used to make cellulose (strengthen cell walls )
🟡made into starch for storage
🟡added to nitrate ions to make protein
🟡turned into fats and oils for storage

67
Q

How you test a leaf for starch ?

A

🌱Put the leaf in boiling water
🌱Put it in a boiling tube with ethanol- removes chlorophyll pigment
🌱Dip the leaf in boiling water to soften it
🌱Add iodine solution
✅If starch is present should to to blue/black

68
Q

How do you test for chlorophyll

A

🌚De-starch (leave in dark) a variegated plant , so that previous starch does not ruin the results
🌞Place in sunlight
🌱Starch test
✅If positive there should be blue/black areas with white ares

69
Q

How do you test for light?

A

🌚De-starch leaf
🌗Make a partially covered leaf
🌱Test for starch

70
Q

How do you test a leaf for carbon dioxide ?

A

🌱Place a leaf of the plant in a closed system with soda lime.
🌱This absorbs the carbon dioxide (reactants) which means the photosynthesis won’t happen.
🌱Starch test
✅Leaf should be orange brown as photosynthesis did not happen

71
Q

How do you test for oxygen?

A

💦🌿Place the aquatic plant in water
🧪Collect bubbles of the gas
✅Make sure it is oxygen by holding out a glowing split and making sure it is relighted

72
Q

How are light and distance related?

A

Light is inversely proportional to the square of the distance:
Light = 1➗distance ^2

73
Q

What are the limiting factors for photosynthesis, and how do they affect the rate of reaction?

A

🔮temperature- increase until the enzymes denature
🔮light intensity- increases
🔮carbon dioxide -increases

74
Q

What is the purpose of simple sugars?

A

They can go into the blood and provide energy

75
Q

What is the purpose of amino acids (from digestion of proteins)?

A

They can be built back up into proteins by protein synthesis

76
Q

What is the purpose of fatty acids and glycerol ( in the digestion of fat)?

A

?

77
Q

What is a limiting factor?

A

Despite an increase in other factors (eg: temperature/carbon dioxide).
The rate of photosynthesis will not increase any more. This can be seen on the graph as a curve levelling off.

78
Q

How can you identify a limiting factor on a graph?

A

The other two conditions will be constant or the same effect to each reactant.
The limiting factor will have a change

79
Q

How does substrate concentration affect enzymes?

A

It will increase the rate of reaction until there are enough enzymes,after that it will keep the rate the same

80
Q

How does the structure of DNA affect the proteins made?

A

🔵The triplet code (codons)
🔵 used to determine amino acids in proteins

81
Q

How could you measure the rate of photosynthesis? (Experiment)

A

Do the oxygen pondweed experiment, count the amount of bubbles produced, in varying factors

GCSE Biology OCR A (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions