Brainscape's Knowledge GenomeTM

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


See full index

Biology > B14 - Variation and Evolution > Flashcards

B14 - Variation and Evolution Flashcards

1
Q

What is variation

A

Differences in the characteristics of individuals in a population

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

What two things contribute to variation?

A
  • Genetics (Nature)
  • Environment (Nurture)

Variation can be caused by a combination of these factors

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

Examples of variation caused by genetics

A
  • Eye colour
  • Gender
  • Blood type
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Examples of variation caused by environment

A
  • Scarring
  • Language
  • Muscle strength
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How does a mutation cause variation

A
  • Mutations are uncontrollable, constantly occuring changes in DNA
  • This may give an organism desired characteristics making it better suited to an environment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is evolution

A

Changes in characteristics in a species from one generation to the next

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

Outline the stages in the theory of evolution by natural selection (5 steps)

A
  • Mutation
  • Survival
  • Reproduction
  • Pass on beneficial alleles
  • More offspring with allelle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is selective breeding

A

Where humans breed animals or plants in order to get offspring with certain desired characteristics

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

Describe the main steps in the process of selective breeding

A
  • Find parents with desired characteristics in population and breed them
  • Breed the offspring with the best characteristics
  • Continue for many generations until all have desried characteristics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Examples of characteristics that could be selected in selective breeding

A
  • Animals that produce lots of milk or meat
  • Domestic dogs
  • Disease resistant plants
  • Types of flowers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Problems with selective breeding

A
  • Lack of variation - leaves organisms vunerable to changes in environment
  • Can unknowingly spread genetic defect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is genetic engineering

A

Modifying the genome of an organism by introducing a gene from another organism to give a desired characteristic

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

Describe the process of genetic engineering

A
  • Enzymes isolate the required gene
  • The gene is the put into a bacterial plasmid which acts as a vector
  • The vector inserts the genes into the cells
  • The genes are insterted in early development allowing the organism to develop with desired characteristics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Uses of genetic engineering

A
  • Bacterial cells to produce insulin
  • Plants + GM Crops - bigger, increased yield, resistant to diseases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Benefits of genetic engineering

A
  • Increased crop yield
  • Faster results compared to selective breeding
  • Herbicide/insect/drought resistance
  • Increased nutritional value
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Problems/risks with genetic engineering

A
  • Gene could get into other species or environment causing herbicide resistant weeds
  • Some people see it as “playing God”
  • Unknown effects on humans
17
Q

2 methods of cloning plants

A
  • Taking cuttings
  • Tissue culture
18
Q

Describe the method of cloning plants by using cuttings

A
  • Old, simple method used by gardeners
  • Branch from parent taken
  • Placed in damp compost with nutrients and hormones
19
Q

Describe the method of cloning plants by tissue culture

A
  • USed to preserve rare plant species
  • Explants are placed in agar that contains nutrients and hormones
  • Platelets grow
  • They are then placed in compost
20
Q

Describe the process of animal cloning by embryo transplants

Using cows for example

A
  • Cow given fertitlity drugs and artificially inseminated with sperm from a bull
  • Zygotes develop into embryos and then taken from cow
  • Embryos are split into smaller embryos
  • All embryos are genetically identical and are placed in surrogate mothers
21
Q

Describe the process of adult cell cloning

A
  • Nucleus removed from egg cell
  • Nucleus from adult cell e.g. skin cell placed in egg
  • Egg is then shocked to start cell division
  • Embryo has same genetic info as nucleus from skin cell
  • Once embryo has developed, it is placed in a surrogate mother
22
Q

Benefits of adult cell cloning

A
  • Save animals from extinction
  • Bring back animals that are already extinct
23
Q

Drawbacks of adult cell cloning

A
  • Could lead to human cloning which is illegal
  • Reduces variation making a species vunerable to environment changes
  • Designer babies

Biology (19 decks)

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