Brainscape's Knowledge GenomeTM

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


See full index

biology > dna & inheritance (new) > Flashcards

dna & inheritance (new) Flashcards

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

sexual reproduction

A

when male and female gametes fuse

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

Recall the male and female gametes found in plants.

A

Pollen and Egg Cells

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

Which process are gametes formed?

A

Meiosis

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

What happens to the number of chromosomes during meiosis?

A

They halve in number (23 Chromosomes)

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

What happens to the number of chromosomes during fertilisation?

A

They are restores to the full number (46 Chromosomes)

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

What is formed after cells in reproductive organs divide by meiosis?

A

Gametes

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

How many times does the cell divide to form 4 gametes?

A

The cell divides twice to form four gametes.

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

What needs to happen for variation to give a survival advantage by natural selection.

A

Environment Changes.

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

State way humans can increase food production by natural selection.

A

Use Selective Breeding.

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

How do malarial parasites reproduce in humans?

A

In humans = Asexually

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

How do malarial parasites reproduce in mosquitos?

A

In mosquitos = Sexually

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

How do fungi reproduce

A

By Spores becoming new fungi when they land in a suitable place

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

2 types of spores?

A

asexually produced - genetically identical
sexually produced - variation

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

Name the plant which reproduces asexually. and how

A

Strawberry plants produce runners which are stems that grow horizontally on the surface of the soil which grows new identical plants along it

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

Name the plant which reproduces by bulb division. and explain what it is

A

Daffodils. new bulbs form on the main bulb and divide off each new bulb can form into a new identical plant

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

Why is DNA classed as a polymer?

A

DNA is made up of two strands of nucleotides in a double helix

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

What is a Gene?

A

A gene is a small section of DNA on a Chromosome.

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

In DNA, what does each nucleotide contain?

A

Sugar and phosphate group with a base attached to the sugar.

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

Name the bases found in DNA.

A

Adenine, Cytosine, Guanine & Thymine.

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

How many bases in DNA are needed to code for an Amino Acid?

A

3 bases = an Amino Acid (also a Gene).

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

What happens when the order of bases are changed in DNA?

A

A different protein is made.

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

DNA is polymer, what is the monomer?

A

Nucleotides.

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

What happens to enzymes when the order of bases are changed in DNA?

A

Leads to change in shape of the enzyme and the active site.

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

How do genetic variants influence phenotype in non-coding DNA?

A

By altering how genes are expressed.

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

Which organelle in the cell synthesises proteins?

A

Ribosomes.

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

Which molecule adds specific amino acids to add to a growing protein chain?

A

Carrier Molecules.

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

Give 3 examples of proteins found in the body.

A

Enzymes, Hormones & Collagen.

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

How often do mutations occur?

A

continuously and spontaneously

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

What happens when a mutation leads to a change in the shape of an enzyme or a structural protein?

A

An enzyme may no longer fit the substrate binding site or a structural protein may lose its strength.

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

What is a function of Non-Coding parts of DNA?

A

Can switch genes on and off. variations in them can affect how genes are expressed

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

Define the term Allele.

A

Different forms of the same gene.

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

Define the term Homozygous.

A

When an organism has two alleles that are the same for an inherited characteristic

33
Q

Define the term Heterozygous.

A

When an organism has two alleles that are different for an inherited characteristic.

34
Q

Define the term Genotype.

A

The genetic makeup of an organism, controls the phenotype.

35
Q

Define the term Phenotype.

A

Characteristics expressed by the organism.

36
Q

Name the 2 characteristics controlled by a single gene.

A

Fur colour in mice and red-green colour blindness in humans.

37
Q

How many genes are required in most characteristics?

not exact value

A

Multiple Genes.

38
Q

State the cause of inherited disorders.

A

Inheritance of certain alleles.

39
Q

What is Polydactyly and what type of allele is it caused by?

A

Having extra fingers or toes and is caused by a dominant allele.

40
Q

What is Cystic Fibrosis and what type of allele is it caused by?

A

A disorder of cell membranes and is caused by a recessive allele.

41
Q

what happens when a protein chain is complete

A

when a chain of ammino acids has been assembled it folds into a unique shape which allows protein to perform a specific function

42
Q

3 types of mutation

A
  • insertions
  • deletions
  • substitutions
43
Q

PGD

A
  • method of genetic embryo screening
  • during ivf u remove 1 cell from each embryo and analyse its genes (pgd)
  • embryos with healthy alleles reimplanted
44
Q

CVS

A
  • method of embryo genetic screening
  • usually between 10 -13 weeks
  • take a sample of cells from the placenta and analyse the genes
  • if embryo has an inherited disorder parents can decide whether or not to terminate
45
Q

arguements for embryo screening

A
  • alleviates suffering
  • treating disorders is expensive
  • during ivf most embryos are destroyed anyway PGD just ensures chosen one is healthy
  • with cvs parents dont HAVE to terminate
46
Q

arguments against embryo screening

A
  • designer babies
  • implies ppl with genetic problems are undesirable - increases prejudice
  • in pgd rejected embryos are destroyed - could have been a human life
  • in cvs parents may terminate a pregnancy they would have otherwise kept
    expensive
47
Q

How many PAIRS of chromosomes to human body cells have?

A

23 pairs (46 in total).

48
Q

What do the first 22 chromosomes control.

A

Characteristics.

49
Q

State the pairs of chromosomes which determine a human’s sex.

A

“Females = XX
Males = XY”

50
Q

How could we influence the development of the phenotype?

A

Change in genotype or environment.

51
Q

What 3 reasons may there be a cause for variation in a population?

A

”* The genes they have inherited (genetic causes)
* The conditions in which they have developed (environmental causes)
* A combination of genes and the environment.”

52
Q

How often does a mutation lead to a new phenotype?

A

Very rarely.

53
Q

Define Evolution.

A

A change in the inherited characteristics of a population over time through a process of natural selection which may result in the formation of a new species.

54
Q

What does natural selection of variants give rise to?

A

Phenotypes best suited to their environment.

55
Q

Give an example of a useful characteristic in selective breeding.

A

”* Disease resistance in food crops.
* Animals which produce more meat or milk.
* Domestic dogs with a gentle nature.
* Large or unusual flowers.”

56
Q

Define Genetic Engineering.

A

A process which involves modifying the genome of an organism by introducing a gene from another organism to give a desired characteristic.

57
Q

Why are Bacterial cells genetically engineered?

A

To produce useful substances such as human insulin to treat diabetes.

58
Q

State the benefits of GM crops.

A
  • Resistant to insect attack & herbicides.
  • GM crops have increased yield.
  • more nutrients - i.e golden rice
59
Q

State the disadavtages of GM crops.

A

“Negative effect on populations of wild flowers and insects.
Some people feel the effects of eating GM crops on human health have not been fully explored.”

60
Q

State the steps of Genetic Engineering.

A

“In Genetic Engineering:
* Enzymes are used to isolate the required gene; this gene is inserted into a vector, usually a bacterial plasmid or a virus.
* The vector is used to insert the gene into the required cells.
* Genes are transferred to the cells of animals, plants or microorganisms at an early stage in their development so that they develop with desired characteristics.”

61
Q

tissue culture

A

a few plant cells are put in a medium with growth hormones like auxin and grow new plants
- quick and little space
- preserves endangered species

62
Q

Why was Darwin’s theory of evolution only gradually accepted?

A

”* The theory challenged the idea that God made all the animals and plants that live on Earth
* There was insufficient evidence at the time the theory was published to convince many scientists
* The mechanism of inheritance and variation was not known until 50 years after the theory was published.”

63
Q

Name the scientist who proposed that changes that occur in an organism during its lifetime can be inherited.

A

lamarck

64
Q

Name the scientist who is best known for his work on warning colouration in animals and his theory of speciation.

A

wallace

65
Q

Name the scientist who is best known for his observation that inheritance of each cahracteristic is determined by “units”.

A

mendel

66
Q

Define the term Fossils.

A

The ‘remains’ of organisms from millions of years ago, which are found in rocks.

67
Q

How are Fossils formed?

A

”* From parts of organisms that have not decayed because one or more of the conditions needed for decay are absent
* When parts of the organism are replaced by minerals as they decay
* As preserved traces of organisms, such as footprints, burrows and rootlet traces.”

68
Q

Why cannot scientists be certain about how life on Earth began.

A

Many early forms of life were soft-bodied, which means that they have left few traces behind. What traces there were have been mainly destroyed by geological activity.

69
Q

What can we learn from Fossils?

A

How much or how little different organisms have changed as life developed on Earth.

70
Q

Name a bacterial strain which is resistant to antibiotics.

A

MRSA.

71
Q

How can we reduce the rate of development of antibiotics strains?

A

”* Doctors should not prescribe antibiotics inappropriately, such as treating non-serious or viral infections
* Patients should complete their course of antibiotics so all bacteria are killed and none survive to mutate and form resistant strains
* The agricultural use of antibiotics should be restricted.”

72
Q

Recall the catagories which Linnaeus classified living things.

A

Kingdom, phylum, class, order, family, genus and species.

73
Q

Why did new models of classification progress?

A

Evidence of internal structures became more developed due to improvements in microscopes, and the understanding of biochemical processes progressed.

74
Q

State the three domains found in Carl Woese system.

A

Archaea, Bacteria & Eukaryota.

75
Q

embryo transplant

A
  • sperm used to artificially fertilise an egg cell
  • embryo that developes is split many times to form clones
  • cloned embryos implanted into different host mothers
76
Q

adult cell cloning

A
  • remove nucleus of unfertilised egg cell
  • replace with nucleus taken from adult cell
  • electrically stimulate egg cell to divide to form embryo
  • implant in host mother
77
Q

pros of cloning

A
  • used to preserve endangered species
  • quickly get lots of ideal offspring with desired characteristic
  • study of animal clones could lead to greater understanding of embryo development , aging and age related disorders
78
Q

cons of cloning

A
  • reduced gene pool
  • cloned animals may not be as healthy

biology (10 decks)

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