Evolution

Question 0

what are the two dating methods used to determine the age of a fossil?

Answer 0

relative dating - determines whether a fossil is older or younger than other fossils
radiometric dating - relies on radioactive isotopes, which decay, or break down, into stable isotopes at a steady rate

Question 1

what is evolution?

Answer 1

change over time ; the process by which modern organisms have descended from ancient organisms

Question 2

how old have scientists determined the Earth to be?

Answer 2

4.2 billion years

Question 3

when did life first appear on Earth?

Answer 3

3.7 billion years ago

Question 4

what were the first life forms?

Answer 4

unicellular, prokaryotic

Question 5

list the following in the order in which they appeared over earth’s history: eukaryotes, prokaryotes, multicellar organisms

Answer 5

prokaryotes , eukaryotes , multicellular organisms

Question 6

what evolutionary event does the endosymbiotic hypothesis explain?

Answer 6

it says that prokaryotic cells entered those ancestory eukaryotes

Question 7

list the evidence for the endosymbiotic hypothesis

Answer 7

mitochondria and chloroplasts contain dna similar to bacterial dna

Question 8

what is the goal of systematics or classification?

Answer 8

to organize living things into groups that have biological meaning

Question 9

what is a cladogram and how can it be used to classify organisms?

Answer 9

it links groups of organisms by showing how evolutionary lines, or lineages branched off from common ancestors
- how closely related they are

Question 10

how can a cladogram be used to determine similarities in DNA sequences and recent common ancestry?

Answer 10

if they are closer together on the cladogram they are more related and have a more recent common ancestor

Question 11

what is a derived character?

Answer 11

a trait that arose in the most recent common ancestor of a particular lineage and was passed along to its decendants

Question 12

what does a node on a cladogram represent?

Answer 12

the common ancestor

Question 13

what scientist incorrectly thought thst evolution could be explained by the inheritance of aquired traits? what does the inheritance if aquired traits mean?

Answer 13

lamarck

traits altered by an individual organism during its life

Question 14

who developed the theory that evolution occurs by the process of natural selection?

Answer 14

charles darwin

Question 15

what is natural selection?

Answer 15

process by which organisms that are most suited to their enviroment survive and reproduce most successfully

Question 16

list four components of the natural selection theory

Answer 16

struggle for existance
variation
adaptation
survival of the fittest

Question 17

how do adaptations such as camouflage and mimicry develop?

Answer 17

nature provides

Question 18

how does the variation needed for natural selection arise?

Answer 18

some variations are better suited to life in their enviroments than others

Question 19

what is a gene pool?

Answer 19

consists of all the genes including all the different alleles for each gene

Question 20

how do u know if a population is evolving in terms of allelic frequencies?

Answer 20

allele frequency is changing

Question 21

what is happening to allelic frequencies in a population that js in genetic equilibrium?

Answer 21

its staying the same

Question 22

list five factora that cause allelic frequencies to change in a population

Answer 22

small population, migration, natural selection, random mating, mutations

Question 23

list four major classes of evidences for evolution

Answer 23

fossil records

comparing of analogy , embryos , & dna

Question 24

what are analgous structures?

Answer 24

body parts that share a common function, but not structure

wing of bee and bird

Question 25

what is homologous structures?

Answer 25

structures shared by a common ancestor. similar in structure
(limbs of alligator and chicken)

Question 26

what are vestigal structures?

Answer 26

structures that lost its usefulness but are inherited from their ancestor and it is still there
(human tail bone)

Question 27

which form of evidence for evolution allows scientists to determine thr amount of time that has passed since two species diverged from a common ancestor?

Answer 27

molecular clock

Question 28

describe how new species evolve

Answer 28

over long periods of time

Question 29

compare directional , disruptive , amd stabilizing selection

Answer 29

dir- one end has higher frequency
dis- out ends have higher frequency
s- center has higher frequency

Question 30

what is convergent evolution?

Answer 30

process by which unrelated organisms independently evolve similarties when adapting to similar enviroments

Question 31

what is divergent evolution?

Answer 31

the process by which a single species evolves over a relatively short time into several different forms that live in different ways

Question 32

why are mass extinctions important?

Answer 32

they allow other organisms to live and take over such as humans when dinosaurs went extinct