Brainscape's Knowledge GenomeTM

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


See full index

Higher Human > Unit 1 - Human Cells > Flashcards

Unit 1 - Human Cells Flashcards

1
Q

Name two types of human stem cell

A

Adult stem cell and embryonic stem cell

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

Give a definition of cellular differentiation

A

Cellular differentiation is the process by which a cell develops more specialized functions by expressing the genes characteristic of that type of cell

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

Give two ways that stem cells differ from other body cells

A

Stem cells are undifferentiated whereas body cells are suited to a specific function

Stem cells can become any cell type of the human body

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

What is a somatic cell?

A

A somatic cell is a body cell that divides by mitosis to form more body cells

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

Give two differences between embryonic and adult stem cells

A

Embryonic stem cells are pluripotent; they can become any cell type. They are found in embryos.

Adult (tissue) stem cells are found in specific regions; bone marrow, muscles etc. They can only become several cell types from the region of extraction.

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

By what process do somatic cells divide?

A

Somatic cells divide by mitosis

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

When germline cells divide by mitosis what do they form?

A

They produce more germline cells

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

When germline cells divide by meiosis what do they form?

A

They form haploid gametes

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

In what type of cell would a mutation be passed on to the offspring?

A

Germline

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

Give one therapeutic use of stem cells

A

They can be used therapeutically to repair damaged or diseased organs and tissue. Current uses include corneal and skin grafts.

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

Give one use of stem cells in research

A

They can be used as model cells to study how diseases develop or for drug testing

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

Give one ethical issue concerning the use of stem cells

A

Is the prevention of suffering more important than the duty to preserve human life? - Embryonic stem cell research forces us to choose between two moral principles; prevent suffering or respect the value of human life?

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

Give a definition of a tumour

A

A tumor is a collection of cancer cells produced by excessive, uncontrolled cell division

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

Give 2 ways that cancer cells are different to other cells

A

They don’t respond to regulatory systems; target cells are unresponsive or absent

Cancer cells fail to attach to their surroundings unlike normal cells

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

How is a secondary tumor formed?

A

Cancer cells fail to attach to their surroundings and spread throughout the body in the bloodstream, forming secondary tumor

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

Name the 3 components of a nucleotide

A

A deoxyribose sugar, a phosphate and a nitrogenous base

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

What type of bonds hold the 2 DNA strands together?

A

Weak hydrogen bonds

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

Which end of a DNA strand has a free deoxyribose sugar?

A

3’ end has a free deoxyribose sugar

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

Name a molecule other than DNA, that is found in chromosomes

A

RNA

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

Name 2 factors essential for the replication of DNA

A

DNA polymerase and ATP

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

Name 2 processed involved in turning a DNA double helix into 2 template strands

A

Transcription and translation

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

Which end of the DNA strand does DNA polymerase add nucleotides to?

A

Adds on the 3’ end

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

Which end has a free phosphate group?

A

5’ end has a free phosphate

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

What enzyme joins DNA fragments together during replication?

A

DNA ligase

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

What is an organism’s phenotype determined by?

A

The phenotype of an individual is the result of the proteins produced by the expression of its genes

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

Are all the genes in a cell expressed?

A

Only a fraction of the genes in any cell are expressed

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

Give 2 types of environment factors that influence gene expression

A

Intracellular and extracellular environmental factors

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

Give 2 processes that are regulated during control of gene expression

A

Transcription and translation

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

Give 3 structural differences between RNA and DNA

A

DNA nucleotides have a deoxyribose sugar, RNA have a ribose sugar

DNA nucleotides have the bases adenine, thymine, cytosine and guanine
RNA nucleotides have the bases adenine, uracil, cytosine and guanine

DNA is a double stranded molecule
RNA is a single stranded molecule

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

What is the function of mRNA?

A

mRNA carries a complementary copy of the genetic code from the DNA in the nucleus to the ribosome in the cytoplasm to be translated

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

Give 2 components of a ribosome

A

They are made of protein and RNA

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

What is the function or tRNA?

A

Carries specific amino acids to the ribosomes that can be assembled to form polypeptide chains

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

What enzyme is responsible for the transcription of DNA to form a primary transcript?

A

RNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What DNA bases are complimentary to the RNA bases A, U, C & G?

A

Adenine + Uracil

Cytosine + Guanine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Give a definition of an intron

A

a non coding region on a DNA sequence (of a primary transcript)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What process joins together the exons of a primary RNA transcript?

A

Splicing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Give a definition of an exon

A

A coding region in a DNA sequence of a primary transcript

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Where does translation of mRNA occur?

A

In the ribosomes in the cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Explain why tRNA molecules are folded

A

Because of base pairing and forms a triplet anticodon site and an attachment site for a specific amino acid

40
Q

Name 2 specific sites present on all tRNA molecules?

A

An anticodon site and an amino acid attachment site

41
Q

How many bases are present in an mRNA codon?

A

3

42
Q

How many bases are present in a tRNA anti-codon?

A

3

43
Q

What is the name of the process that uses the mRNA code to produce a protein?

A

Translation

44
Q

What type of bond hold amino acids together in a protein?

A

Peptide links

45
Q

Name 2 processes that allow a single gene to code for many proteins

A

Alternative splicing & post-translational modification

46
Q

Give 2 examples of post-translational modification of proteins

A

Making changes to the chemical structure of the polypeptide chain or cutting and combining of the chain

47
Q

Give 3 types of forces which hold proteins in their 3D shape

A

Peptide bonds, hydrogen bonds and interactions between individual amino acids

48
Q

If a gene is mutated what will the consequence be for the protein it codes for?

A

Mutations of genes result in no protein or an altered protein being expressed

49
Q

Give a definition of a substitution mutation

A

One nucleotide removed from a DNA sequence and replaced by another with a different base

50
Q

Give a definition of an insertion mutation

A

An additional nucleotide added into a DNA sequence

51
Q

Give a definition of a deletion mutation

A

A nucleotide removed from a DNA sequence but not replaced by another this is sometimes called a frame shift mutation

52
Q

Give 3 examples of single nucleotide substitution gene mutations

A

Missense, nonsense

53
Q

Give 2 examples of frame-shift gene mutations

A

Insertion and deletion

54
Q

Give 3 examples of chromosome structure mutations

A

Deletion, duplication and translocation

55
Q

Give a definition of bioinformatics

A

The use of computers and statistics in analysis of sequence data

56
Q

What type of medicine depends on an understanding of an individuals genetic risk of disease?

A

Personal medicine

57
Q

What does PCR mean?

A

Polymerase chain reaction

58
Q

What enzyme is used for replication if DNA during PCR?

A

Taq polymerase

59
Q

What component of PCR mix ensures that only specific target sequences are replicated?

A

DNA probes

60
Q

What property of DNA polymerase requires primers to be present in the PCR mix?

A

DNA polymerase needs an optimum temperature

61
Q

What effect does heating have on the DNA during the PCR cycle?

A

The DNA becomes denatured

62
Q

What process takes place during cooling in the PCR cycle?

A

The primers can bind to the separated DNA strands

63
Q

Describe the structure and function of a DNA probe

A

A short piece of DNA complementary to a target sequence of DNA

64
Q

What property of an individuals DNA allows them to be identified by DNA profiling?

A

Variable repetitive sequences

65
Q

Are anabolic pathways energy requiring of releasing?

A

Requiring

66
Q

Are catabolic pathways energy requiring or releasing?

A

Releasing

67
Q

What modern theory of enzyme activity has replaced the lock and key model?

A

Induced fit

68
Q

In what way do enzymes affect the activation energy of a reaction?

A

Enzymes are biological catalysts that speed up the rate of a reaction by lowering the activation energy required for the reactions to proceed

69
Q

Describe how the concentration of an end product can affect the direction of a reaction

A

If the concentration of an end product is too high feedback inhibition can occur

70
Q

Where on the enzyme does a competitive inhibitor bind?

A

Competitive inhibitors have a similar structural shape to the normal substrate of the enzyme so can fit in the active site

71
Q

How does a non-competitive inhibitor affect an enzymes active site?

A

Non-competitive inhibitors have a different structure and so cannot fit the active site but instead they bind to another part of the molecule. This alters the shape of the active site so much so it cannot combine with the substrate molecule

72
Q

Describe feedback inhibition of a metabolic pathway

A

Feedback inhibition occurs when an end product inhibits the activity of an enzyme that catalysed a reaction earlier in the pathway

73
Q

What is the role of dehydrogenase enzymes in respiration?

A

They remove hydrogen ions and high energy electrons from intermediates in the citric acid cycle

74
Q

ATP is used to transfer energy in cells. Give another cellular use of ATP?

A

ATP is a storage molecule for chemical energy

75
Q

What part of the respiratory pathway breaks down glucose to form pyruvate?

A

Glycolysis

76
Q

Where in the cell does glycolysis occur?

A

In the cytoplasm

77
Q

Describe the role of phosphofructokinase in glycolysis?

A

It catalyses an irreversible reaction in the glycolysis pathways which essentially ensures that the pathway is switched on

78
Q

Give another name for the Citric Acid Cycle?

A

The krebs cycle

79
Q

Where in the cell does the CAC occur?

A

In the matrix of the mitochondria

80
Q

Name 3 chemicals made by the CAC

A

ATP, CO2 and citrate

81
Q

Name 2 co-enzymes that can accept hydrogen ions from dehydrogenase enzymes

A

NAD and FAD

82
Q

Where in the cell does the electron transport chain take place?

A

The inner membranes of the mitochondria

83
Q

What high energy molecule is released when NADH and FADH2 are oxidized in the electron transport chain?

A

Electrons

84
Q

What type of ions flow through the membrane protein ATP synthase causing it to make ATP?

A

Hydrogen ions

85
Q

What is the final acceptor in the electron transport chain?

A

Oxygen

86
Q

Name 4 substrates for respiration other than sugar molecules

A

Pyruvate, acetyl coenzymeA, oxaloacetate and amino acids

87
Q

What enzyme in respiration is inhibited by ATP and citrate?

A

Phosphofructokinase

88
Q

State the function of créatine phosphate in muscle cells

A

A substance that acts as a reserve of phosphates & energy in muscle and brain cells. It can be broken down rapidly to release phosphate and energy during the first 10 seconds of intense muscular effort

89
Q

Under what conditions do muscles produce lactic acid

A

In the absence of oxygen during physical activity

90
Q

What type of muscle fibres are best suited to endurance activities?

A

Slow-twitch muscle fibres

91
Q

What type of muscle fibres are best suited to produce short bursts of activity?

A

Slow-twitch muscle fibres

92
Q

Which type of muscle fibre contracts more quickly?

A

Fast-twitch fibres

93
Q

Describe the importance of the regulation of gene expression

A

Because it conserves cell resources and energy by producing proteins only when they are required

94
Q

Define substitution nonsense

A

substitution mutation in which a codon is changed to a stop codon, shortening the resulting protein

95
Q

Define missense

A

A substitution mutation; a single nucleotide change results in a codon for a different amino acid

Higher Human (3 decks)

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