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Flashcards in 7 Evolution Deck (36)
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1
Q

In three points explain how natural selection leads to evolution?

A

Mutation
Individuals with characteristics most suited to environment survive
Genes passed to next generation

2
Q

What does oestrogen inhibit?

A

FSH

3
Q

describe what happens at a synapse during reflex?

A

Chemical release
Diffuses across the gap
Transmits impulse across synapse
Between neutrons

4
Q

What scientist suggested an alternate explanation for evolution?

A

Lamarck

5
Q

What is classification?

A

The organisation of living things into groups according to their similarities

6
Q

Why do most scientists only accept darwins theory?

A

More evidence

Genes discovered

7
Q

What inhibits FSH production?

A

Oestrogen

8
Q

How does natural selection work?4

A
  • by selecting the organisms best adapted to a particular habitat
  • different organisms in a species show a wide range of variation because of their genes
  • those with the characteristics most suited to their environment are most likely to survive and breed w success
  • these genes that have produced successful characteristics are then passed on to the next generation
9
Q

What is the evidence that evolution has taken place?

A

That evolution takes place through natural selection

10
Q

What does the theory of evolution state?

A

Present day organisms have evolved from simpler organisms over long periods of time (billions of years)

11
Q

Why was Darwins theory of evolution only gradually accepted?

A
  • there was conflict between the belief that God made all the animals and plants on earth
  • Insufficient evidence
  • no way of explaining variety and inheritance ( because genetics weren’t understood until another 50 years)
12
Q

How does classification help us understand evolution?

A

It helps us understand ecological and evolutionary relationships

13
Q

Explain how natural selection occurs?

A

Mutation / variation in population
More advantageous get more food /territory/ light etc
These survivors breed more
Pass on genes

14
Q

Why were people against darwins ideas?

A

Religious objection

Insufficient evidence

15
Q

What wasent known in the 1800s

A

Genes and DNA weren’t discovered

16
Q

What is mutation?

A

A change in genetic material (DNA) which results in a new form of a gene

17
Q

Lamarcks theory? Eg with elephant trunk

A

Ancestor stretches nose to reach food

Passed on this stretched nose to offspring

18
Q

Why were people against darwins ideas?

A

Religious objection

Insufficient evidence

19
Q

What is a mutation?

A

A change to the genetic material / DNA

In an organism

20
Q

Who has Jean-Babyiste Lamarck?2

A
  • a French biologist

- who proved the inheritance of acquired characteristics

21
Q

In three points explain how natural selection leads to evolution?

A

Mutation
Individuals with characteristics most suited to environment survive
Genes passed to next generation

22
Q

What is a hormone?

A

A chemical messenger
Produced by a gland
That acts on a target organ
Controls body functions

23
Q

What stimulates the maturing of the egg?

A

FSH

24
Q

What did people think before Darwin about evolution?

A

God made all living things

25
Q

What does FSH stimulate?

A

Oestrogen production

Egg maturing

26
Q

What is the theory of evolution?3

A
  • the theory of evolution states that all the species which are alive today
  • many more which are now extinct
  • evolved from simple life forms that first developed more than 3 billion years ago
27
Q

How can animals be adapted against predators?

A

Camouflage - less likely to see prey
Warning colours - likely to confuse prey with a poisonous organism
Prickles - sharp and hurts predator
Long limbs/ streamlining - increase speed to outrun predator
Position of eyes - prey can escape sooner
Poison - spit out prey not attack again

28
Q

What is a categoric variable?

A

One best described by a label

Eg colour of eyes

29
Q

What is a continuous variable?

A

Quantities found by measuring a variable eg temperature

30
Q

How is a measurement repeatable?

A

If same person can repeat it using same method and equipment and get same results

31
Q

How is a measurement reproducible?

A

If someone else can do it and get the same results

32
Q

Increasing accuracy?

A

Repeat measurements and find a mean
Repeating with different instruments
High quality instruments
Be careful

33
Q

Increasing precision?

A

Repeat tests the same small scale divisions

34
Q

What does darwins theory state?

A

That all living things have evolved from simple life forms that developed more than 3 billion years ago

35
Q

Why was natural selection only gradually accepted?

A

Challenged the idea that God made all animals + plants that live on earth
Insufficient evidence
Inheritance and variation was not known until 50 years

36
Q

Why couldn’t scientists decide between lamarcks theory and darwins theory?

A

Insufficient evidence for both
Mechanism of inheritance was not known
Genes not discovered