B2 Fossils

Question 1

Factors cause extinction (6)

Answer 1

Changes to environment over geological time
Predators
Disease
Comp for food
Ice age
Volcanic eruption
Asteroid impacts

Question 2

How fossils formed (3)

Answer 2

Hard parts not decay
When conditions for decay absent
Parts replaced by other materials as they decay
Preserved traces of organisms eg footprints, burrows, rootlet traces

Question 3

Fossil (3)

Answer 3

Remains of organism
Found preserved in ice or rock
From millions of years ago

Question 4

Fossil record show

Answer 4

how species changed overtime

sim and diff between modern and older

Question 5

Prob of fossil record

Answer 5

gap
incomplete part of organism: most soft bodied rarely preserved, destroyed by geological activity
still fossils to be fond
right conditions rare

Question 6

Extinction

Answer 6

permanent loss of all members of species

Question 7

Speciation

Answer 7

formation of new species from pre existing ones

Question 8

Endemic

Answer 8

species found in only one part of world