Brainscape's Knowledge GenomeTM

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


See full index

biology > P1B4 - Natural selection + Genetic modification > Flashcards

P1B4 - Natural selection + Genetic modification Flashcards

1
Q

What is evolution?

A

A change in one or more characteristics of a population over a long period of time

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

How do scientists date/age fossils

A

Depths of fossil in layers of sedimentary rock (closer=recent)

Stone tools (detail=recent)

Closely related species have the same genes in their binomial name

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

What is the binomial system?

A

Kingdom
Phylum
Class
Order
Family
Genus
Species

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

Who is Carl Linnaeus? (1707 - 1778)

A

He suggested humans evolved from apes, developing the binomial system

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

What is closely related to Homo sapiens?

A

Ardi - 4.4 mil years old
Lucy - 3.2 mil years old
Homo habiliis - 2.4-1.4 mil years old
Homo erectus - 1.8-0.5 mil years old

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

The trends in human evolution?

A

Increasing brain volume
Increasing height
Decreasing hair
Decreasing arm length to body ratio

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

What plays a part in natural selection?

A

Genetic variation
Survival of the fittest
Successful breeding
Best characteristics survive

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

How do stone tools provide evidence for human evolution?

A

Old stone tools are simple and were used for cutting meat, recent tools are more sophisticated and shaped for specific functions .

Thus, humans evolved to become smarter and more able to use their hands

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

Why do some bacteria become resistant to antibiotics?

A

Natural selection neatly explains this phenomenon:
Bacteria reproduce rapidly.
Mutations occur during reproduction.
If a mutated bacterium is resistant to antibiotics, it will survive exposure to antibiotics and go on to reproduce.
This bacterium will represent the original ancestor of a new resistant strain.

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

What 3 domains did Carl Woese propose?

A

Archaea - primitive bacteria. (Unused DNA)

Bacteria - true bacteria. (All DNA used)

Eukaryota - organisms possessing complex sub-cellular structures (protists, fungi, plants & animals). (Unused DNA)

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

What is tissue culturing?

A

Growing genetically identical cells in a lab under sterile conditions (without contamination from microorganisms).

Growing cells or tissues in a liquid containing nutrients or using agar.

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

How do we prepare an uncontaminated bacterial culture using aseptic techniques?

A
  1. Sterilise equipment/culture with an autoclave (applies heat under pressure to kill pathogens). Disinfect surfaces and create a convection current using bunsen.
  2. Sterilise inoculating look by passing it through bunsen.
  3. Remove culture lid and flame rim of bottle before and after bacteria collection.
  4. NO equipment should be PUT DOWN during the process!
  5. Spread bacteria on agar by lifiting petri dish SLIGHTLY, gently spreading loop across surface of agar.
  6. Seal dish with tape and store upside down at 25C (To prevent harmful bacteria from gorwing) for 48 hours.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why is Selective breeding in crops useful?

A

Disease resistant crops improves yield (food production productivity).

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

Why is selective breeding in animals useful?

A

In farming, animals that produce more milk or meat are also useful for yield-related reasons

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

What are some dangers of selective breeding?

A

Reduced variation
Inbreeding - some breeds become particularly susceptible to disease or inherited defects.

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

What’s an example of a antibiotic resistant bacteria?

A

MRSA

17
Q

What are some measures doctors take to reduce antibiotic resistance?

A

Doctors should avoid prescribing antibiotics unnecessarily.
Patients must finish a course of antibiotics to make sure that all of the bacteria are killed.
Reduce use of antibiotics in agriculture (eg. cattle feed).

18
Q

What are the three different ways of forming fossils?

A

Mineral replacement
Hardening soft materials
Preservation when decay isn’t possible.

19
Q

How do you determine when a stone tool was in use?

A
  • Determine how deeply the artefact was buried. The deeper the object was stored, the older the object.
  • Use known dates of other items or fossils found at that level.
  • Compare the design to other stone tools that are already dated.
20
Q

What is carbon dating a stone tool?

A

Tells us when the rock was originally formed

21
Q

How many million years ago have the oldest stone tools been dated back to?

A

2.6 Million years ago

22
Q

Why is the fossil record incomplete?

A
  • A lot of early life forms were soft-bodied. So, they did not leave many noteworthy traces.
  • Geological activity has also caused the destruction of many traces of ancient life.
  • Because of this, scientists don’t know the origins of life on Earth.
23
Q

What is Australopithecus afarensis’ nickname?

A

Lucy

24
Q

Why can’t decomposers act in peat bogs?

A

Acidity

25
Q

Who is Carl Woese?

A

A scientist who proposed the ‘Three Domain system’

26
Q

What is genetic engineering?

A

Modifying an organism’s genome by introducing a gene from another organism to produce a desired characteristic.

27
Q

How is vitamin A rice an example of genetic engineering?

A

A gene that produced vitamin A was taken from bacteria and added to rice, producing golden rice that was rich in Vitamin A.

28
Q

What can a lack of vitamin A lead to?

A

Blindness

29
Q

What’s the process of genetic engineering?

A
  1. Select an organism with the DESIRED CHARACTERISTIC
  2. Use RESTRICTIVE ENZYME to cut out the useful gene from DNA
  3. The cutting leaves strands of DNA with jagged ends called
    ‘STICKY ENDS’
  4. The RESTRICTIVE ENZYME is used to cut open DNA plasmid with the same sticky ends.
  5. The DC DNA is joined with the open plasmid using a LIGASE ENZYME
  6. The new DNA is inserted into cell and grown in a CULTURE
  7. Thus producing an organism with the desired characteristic.
30
Q

What are some examples of things we can use genetic engineering for?

A
  • Transferring genes into bacteria, animals and plants.
  • BT insect resistance
31
Q

What reasons do we selectively breeding varieties of fruit/veg?

A

Increased yields
Disease resistance
Coping w certain envrionment conditions
Fast growth
Flavour

32
Q

What are some concerns about genetic engineering?

A

Uncertain long-term effects
Unethical

33
Q

What are some disadvantages of GM crops?

A

Reduce biodiversity
Long-term effects with consumption
Resistance to herbicides (superweed)

34
Q

How are organismss classifried into the 5 kingdoms?

A

Animals (Heterotroph)
Plants (Autotroph)
Fungi - Feed off dead matter
Protists (Unicellular)
Prokaryotes (No nucelus + Unicellular)

35
Q

How is selective breeding carried out?

A
  1. Select organisms with the DESIRED CHARACTERISTICS (Phenotype)
  2. Breed together
  3. Give time for offspring to GROW
  4. Due to sexual reproduction the outcome isnt GUARANTEED.
  5. Repeated over many generations
36
Q

How can bacteria growth be used to test antibiotic efficacy?

A

Paper discs are soaked in antibiotics
- Different antibiotics
- 1 antibiotic at diff concentrartion

The larger the zone of inhibition the more effective the antibiotic is agaainst that specific bacteria.

37
Q

How are tissues cultured in plants>

A

Growing cells or tissues in a liquid containing nitrients or agar.

This means it grows Genetically identical cells quickly producing a clump of undifferentiated cells ( CALLUS! )

The CALLUS is treated with hormones and the cells differentiate n become specialised

38
Q

What are advanbtages of tissue culture?

A

Tissue culture prodcues GM crops that will all have the SAME DC.

Tissue C produces rare plants and plants that are difficult to grow form seeds quicker.

Tissue C produces larger amounts in one cycle (Yield)

39
Q

WHAT ARE THE STAGES TO EVOLUTION?

A

G enetic variation
E nvironmental change
N atural selection
I nherited
E volution

biology (9 decks)

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