Brainscape's Knowledge GenomeTM

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


See full index

Evolution and Genetics > Task 1 > Flashcards

Task 1 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What are eukaryotes? (Nettle)

A

Cell of animals and human (involving nuclei and mitochondria), prokaryotes for bacteria

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

What are eukaryotes made up off? (Nettle)

A

Out of proteins which in turn are made out of chains of amino acids; there are 20 types of them and their sequence, determine what properties the proteins will have

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

What are the proteins main functions in cells like eukaryotes? (Nettle)

A

1) giving cells their shape,
2) Form Connection tissues,
3) hormones/antibodies or enzymes

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

What 3 phases mark the history of genetics? (Nettle)

A
  1. Classical genetics: concept of gene made by Mendel, found out what genes did, not what made of yet;
  2. Molecular genetics: the DNA was found and Watson and Crick made research about resolution of it (1953). Finally understanding of how genes encode and transmit info;
  3. Genomics: around 80s with technology could read DNA sequences directly.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 3 principles of genetics? (Nettle)

A
  1. Genes - particles of inheritance passed on from parents to offspring, determining phenotypical characteristics
  2. Alleles - alternating form in which genes come in,
  3. Individuals have 2 copies of each gene, one copy from each parent (diploid-sexual)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are organisms with one and with two copies of each gene called? (Nettle)

A

Haploid - one copy (asexual)

Diploid - two copies (sexual)

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

What are the two functions of genes? (Nettle)

A
  1. Influence physical characteristic of individual (phenotype) through the genotype.
  2. Info passes from parent to offspring by replicating themselves to produce new individual with the same genotype
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the central dogma of genetics? (Nettle)

A

Changes in DNA sequence can lead to changes in proteins, but changes in proteins cannot change sequence of DNA

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

What are somatic cells? (Nettle)

A

Cells of the body other than the gametes -> making more phenotypes (e.g. cells in skin)
- Mitosis

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

What are gametes? (Nettle)

A

Cells that can make another being, produced by meiosis (e.g. spermcells)
-> carry half a genome

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

Where can DNA be found?

A

In the nucleus, wound around histones, often configurates into chromosomes. In diploid organisms, come in pairs-> humans have 23 pairs: 46 chromosomes (22 are autosomes and 1 pair is sex)

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

How does base pairing look like for DNA?

A

Just C binds to G and A to T. Because of that 2 strands mirror each other ( double helix). They are bound together through weaker, hydrogen bonds

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

What are codons?

A

Triplets of bases coding for a specific amino acid.

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

What is a genetic code?

A

Mapping from particular codons in mRNA to particular amino acids, in the assembled proteins (e.g. GCC = Alanine)

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

What is Mitosis?

A

Normal cell division process whereby a cell produces a daughter that is genetically almost identical to itself

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

What is Meiosis?

A

Special cell division process that produces a haploid gamete from a diploid cell -> recombination occurs during meiosis

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

What is DNA?

A

Deoxyribonuceleic acid: long-chain molecule entailing 2 strands bound to each other and twisted around each other in a double helix
- each strand is made up of a backbone of sugar and phosphates

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

How can DNA make phenotypic material?

A
  1. The 2 strands are broken apart and a single-strand molecule called messenger RNA forms along the anti-sense strand of the open DNA
  2. RNA is chemically similar to DNA, but the T base is replaced by U (Uracil)
    - Transcription & Translation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is Transcription?

A

The process of copying DNA sequences into sequences on a RNA molecule -> takes place in the nucleus

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

What is Translation?

A

The RNA zips itself back up and is transported outside the nucleus into ribosomes that build proteins with the help of amino acids

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

How is the genetic code robust to errors?

A

Through synonymous and nonsynonymous substitutions

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

What is a synonymous substitution?

A

Reading the third base wrongly won’t affect the amino acid sequences

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

What is a nonsynonymous substitution?

A

Error in reading the first base leads to a chemically similar amino acid

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

What are Exons?

A

Codons that are translated into proteins

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

What are Introns?

A

Non-coding sequences, usually transcribed but not translated

26
Q

Are there more Introns or Exons?

A

In general, there tend to be much more introns than exons and only just over 1 % of the genome actually code for proteins

27
Q

What could be the function of non-coding DNA?

A
  • is also transcribed into RNA and may have regulatory functions
  • may also enhance genome’s evolvability
  • transposable elements promote the reshuffling and reduplication of genetic material during meiosis
28
Q

How does sexual reproduction ‘shuffle’ the genes?

A
  1. Recombination/Crossing-over
  2. Independent segregation and linkage
  3. Transposable element insertions and segmental duplication
  4. Whole genome duplication
29
Q

What is polymorphism?

A

A locus for which there is more than one allele in the population
-> most has no phenotypic effect, but are also harmful

30
Q

What types of polymorphism are there?

A
  1. Single nucleotide polymorphism
  2. Single sequence repeats
  3. Segmental duplications
  4. Different genomes between two copies
31
Q

How does the process from Genotype to Phenotype look like?

A
  1. DNA sequence change –(transcription and translation)–>
  2. Amino acid change –(Phenotypic function of protein)–>
  3. Phenotypic change
32
Q

What types of studies are used to hunt genes?

A 
Linkage studies (w/ families)
Association studies  (w/ many participants)
33
Q

What are polygenic traits?

A

Variation in the phenotype is related to which allele is present across a number of genes (e.g. height)

34
Q

What did the study on prairie voles (PV) show regarding genes and behavior?

A

Prairie voles (rodents) form long-term bonds after mating

  • Hormone arginine vasopressin causes a pair bond to form -> released in male’s brain on mating with the female
  • The gene that produces V1a has been localised
  • > Young created genetically engineered mice that had the PV version of this sequence  behaviour changed
35
Q

What human study showed the linkage between genes and behavior?

A

Monoamine oxidase A gene study
-> Dutch family in which males had several conduct disorders missed MOAO activity (enzyme helps regualte serotonin) due to gene base changes

36
Q

What is a point mutation?

A

A change in a single nucleotide pair of a gene

37
Q

What are single nucleotide pair substitutions?

A

Substitutions of one base pair for another because of errors when DNA is copied

38
Q

What types of single nucleotide pair substitutions are there?

A
  1. Transitions - changes between C/G or G/A
  2. Transversions -interchanges of purine for pyrimide bases
  3. Deletion of a base
39
Q

What is a silent mutation?

A

Substitutions that have no effect on the encoded protein

40
Q

What is a missense mutation?

A

Substitution that changes one amino acid to another one

41
Q

What is a Nonsense mutation?

A

A mutation that causes translation to be terminated prematurely

42
Q

What do nucleotide pair insertions or deletions cause?

A

Frameshift mutations, which alter the reading frame of the genetic message;

43
Q

What are mutagens?

A

A number of physical and chemical agents which interact with DNA in ways that cause mutations

44
Q

What is differential gene expression?

A

Almost all cells contain an identical genome -> the differentiation into functions occurs because different subsets of genes are expressed.

45
Q

What do chromatin-modifying-enzymes do?

A

They provide initial control over gene expression by making a region of DNA more or less able to bind to a transcription machinery.

46
Q

What happens during histone modification?

A

Acetyl groups attach to the lysine of histone tails

47
Q

What happens during histone acetylation?

A

Acetyl groups attach to the lysine of histone tails

48
Q

What happens during histone deacetylation?

A

Acetyl groups are removed from the tails

49
Q

What does histone methylation do?

A

It promotes condensation of the chromatin

50
Q

What does the histone code hypothesis suggest?

A

It proposes that specific combinations of modifications help determine chromatin configuration and influence transcription

51
Q

What happenes if DNA is methylated?

A

If you have a methylated regulator in front of a gene, it represses gene expression, by lowering the amount of mRNA; which lowers protein
-> de-methylated regulated DNA enhances gene exlression

52
Q

What is Epigenetic inheritance?

A

Traits transmitted by mechanisms that don’t directly involve the nucleotide DNA sequence

53
Q

How can chromatin structure be regulated?

A

Through histone modification and DNA methylation

54
Q

How is transcription initiation regulated?

A

Via proteins that bind to DNA and either facilitate or inhibit binding of RNA polymerase

55
Q

What is DNA methylation?

A

Tagging specific points in the DNA molecule with a methyl group that silences the genes -> effects are reversible, which helps individuals change when their surroundings change

56
Q

What is the relationship between DNA methylation and histone modification?

A

They interact with and depend on each other, even though they have somewhat opposite effects

57
Q

How durable are DNA methylation and histone modificaiton?

A

DNA methylation: imposes permanent (or at least stabe) regulation
Histone modification: is more labile and reversible

58
Q

What evidence was found concerning epigenetics and food?

A

Agouti Mouse Clone - mutant code turned many yellow; food with extra methyl -> turned mutation off and coat in offspring was brown
Dutch famine - methylation of IGF2 gene was decreased in people whose mothers starved first three months of pregnancy

59
Q

What happens in rats who are nurtured less?

A

Increased methylation of the gene for BNDF, which is a neural growth factor in the prefrontal cortex or in reduction of glucocoricoid receptors (important for immune system)

60
Q

How can the increased methylation of the gene for BNDF in rats be explained?

A

Chronic stress triggers an increase in histone methylation that suppresses gene activity by keeping the DNA containing BNDF tightly wound

Evolution and Genetics (3 decks)

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