B15 - Evidence for evolution

Question 1

fossils

Answer 1

remains of organisms from millions of years ago
-found preserved in rocks, ice

Question 2

Fossil formation - absence of decay

Answer 2

• conditions of decay are not met
  -little o2 or low temp or toxic gas to kill bacteria

Question 3

Fossil formation - minerals

Answer 3

• impessions of organisms is made in mud
• filled with minerals and become fossilised

Question 4

fossil formation - traces of organism

Answer 4

• footprints
• burrows
  -droppings

Question 5

incomplete fossil record due to

Answer 5

• early life forms = soft bodied so little fossils
• destroyed due to volcanoes
• formation conditions were rare so little fossilised

Question 6

Fossil record

Answer 6

• shows changes in organisms
• development and environment of that time

Question 7

fossil record limitation

Answer 7

• small pieces were found only

Question 8

Extinction

Answer 8

permenent loss of all members of a species

Question 9

how does extinction occur

Answer 9

• conditions change
• less adapted species die out
• better adapted individuals survive

Question 10

Reasons for extinction

Answer 10

• change to environment
• temp
  -new predator
  -disease
• successful competitors
• volcanoes

Question 11

Reasons for extinction - new predators

Answer 11

• wipes out prey if they cannot adapt to survive

Question 12

Reasons for extinction - new disease

Answer 12

• likely on islands where population in close together

Question 13

Reasons for extinction - successful competitor

Answer 13

• new mutations = advantage
• better suited

Question 14

geological time

Answer 14

changes of the environment /climate that take place over billions of yrs

Question 15

Fossil evidence on extinction

Answer 15

shows mass extinction
- caused by a single catastrophic event

Question 16

resistant bacteris will

Answer 16

survive and reproduce
-population increases
-antibiotics are no longer active against strain of pathogen
-spreads rapidly

Question 17

Prevention for antibiotic resistant bacteria

Answer 17

• don’t overuse antibiotics
• finish course of medicine always
  -restrict agricultural use

Question 18

Prevention for antibiotic resistant bacteria - finish course of medicine always

Answer 18

-ensures bacteria is killed so none survive to mutate into resistant bacteria

Question 19

Prevention for antibiotic resistant bacteria -restrict agricultural use

Answer 19

• prevent spread of antibiotic resistant bacteria from animal to human

Question 20

which bacteria is resistant

Answer 20

MRSA

Question 21

New antibiotics

Answer 21

• isn’t easy to find chemicals that will kill bacteria without damaging cells
• expensive
• slow development
• unlikely to keep up w resistant strains

Question 22

how do bacteria become resistant

Answer 22

-constantly mutating/reproducing w mutations

Question 23

why does bacteria evolve rapidly

Answer 23

-reproduce at a rapid rate