Natural Selection

Question 1

EVOLUTION

Answer 1

a change over time

Question 2

BIOLOGICAL EVOLUTION

Answer 2

genetic changes in a population that are inherited over generations due to natural selection

Question 3

MACRO EVOLUTION

Answer 3

the development of new species from earlier life forms over many generations

Question 4

MICRO EVOLUTION

Answer 4

variation that occurs within a species. small changes originate in the gene pool, resulting in small changes in the genotype which are passed onto offspring

Question 5

SPECIATION

Answer 5

where a new species develops from existing species over time

Question 6

FOSSIL RECORD

Answer 6

the accumulation of all listed and known fossils of different ages that have been discovered

Question 7

CONDITIONS NEEDED TO FOSSILIZE

Answer 7

• rapid burial
• high pressure
• low oxygen
• hard-body

Question 8

FOSSILS

Answer 8

A fossil is the remains, imprints or traces of an organism usually preserved in rock.

Question 9

HOMOLOGOUS STRUCTURES

Answer 9

Equivalent structures with the same body plan that perform different functions

Question 10

ANALOGOUS STRUCTURES

Answer 10

structures that happen to perform the same function but that did not originate from a common ancestor.

Question 11

MODIFICATION WITHIN A SPECIES

Answer 11

many species changed over millions of years to form the species we know today

Question 12

BIOGEOGRAPHY

Answer 12

the study of the distribution of existing and extinct plant and animal species in specific regions

Question 13

GENETICS

Answer 13

• the study of inheritance and heredity

Question 14

COMPARATIVE BIOCHEMISTRY

Answer 14

• comparing molecular composition of living organisms

- is essentially the same in all orgs, supporting the fact that all life shares a common ancestor.

Question 15

VESTIGIAL STRUCTURES

Answer 15

structures that, in some organisms, decrease in size over evolutionary time with disuse

Question 16

COMPARATIVE EMBRYOLOGY

Answer 16

when vertebrate embryos are compared to each other at various early stages of development they show certain similarities

Question 17

ALL VERTEBRATE EMBRYOS HAVE

Answer 17

• a tail bud
• limb buds
• two-chambered heart

Question 18

HYPOTHESIS

Answer 18

an informed assumption because it provides a proposed solution to a problem or explanation

Question 19

THEORY

Answer 19

a well substantiated explanation or hypothesis that makes sense of a natural phenomenon

Question 20

LAMARCK’S THEORY

Answer 20

• the use or disuse of organs may have an effect on the size of the organ over time
• during their lifetime, organisms acquire changes in characteristics that their offspring inherit

Question 21

PROCESSES THAT CONTRIBUTE TO VARIATION

Answer 21

• Mutations
• Meiosis (Crossing over; Random arrangement of chromosomes)
• Chance fertilisation
• Mating

Question 22

REASONS FOR LAMARCK’S REJECTION

Answer 22

• the discovery of modern genetics

- was the first scientist to propose that “something” passed characteristics of parents onto the offspring

Question 23

DARWIN’S OBSERVATIONS

Answer 23

• individuals of a pop produce more offspring than required to ensure survival
• great deal of variation
• some individuals are better adapted and are more likely to reproduce
• characteristics are transferred from the surviving parents to their offspring

Question 24

NATURAL SELECTION

Answer 24

the mechanism of evolution where nature selects the fittest individuals for survival

Question 25

WHAT NATURAL SELECTION REQUIRES

Answer 25

- variation in the pop - characteristics resp for variation must be hereditary - more offspring must be produced than necessary

Question 26

ARTIFICIAL SELECTION

Answer 26

the deliberate breeding of plants and animals for desired characteristics that would not necessarily benefit survival

Question 27

DIFF BETWEEN ARTIFICIAL AND NATURAL

Answer 27

N - environment acts as selection pressure, A - humans select N - selected charact are advantageous for survival, A - not necessarily adv N - maintains variation, A - dec variation

Question 28

SIMILARITIES BETWEEN NATURAL AND ARTIFICIAL

Answer 28

- variation occurs in a particular pop - variation is hereditary - same outcome (pop changes over time)

Question 29

CONTINUOUS VARIATION

Answer 29

- occurs when there is a range of phenotypes for the same characteristic - it normally forms a continuous spectrum ranging from one extreme to another eg. ) height in humans

Question 30

DISCONTINUOUS VARIATION

Answer 30

when phenotypes fit into separate categories with no intermediate forms - only a single pair of alleles occurs eg. ) sex

Question 31

SPECIES

Answer 31

a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding.

Question 32

POPULATION

Answer 32

a community of organisms among whose members interbreeding readily occurs.

Question 33

EXTINCTION

Answer 33

the loss of species which decreases the range of organisms on earth, decreasing the biodiversity.

Question 34

GEOGRAPHIC SPECIATION

Answer 34

when a new species arises from an existing species , when the pops are separated by a geographical barrier

Question 35

EVIDENCE OF EVOLUTION

Answer 35

- fossil records - descent w modification - biogeography - genetics

Question 36

DESCENT WITH MODIFICATION

Answer 36

how the basic body plan of organism groups were modified to adapt to their diff environments

Question 37

BIOGRAPHICAL REGIONS

Answer 37

- large mountain ranges - deserts - oceans

Question 38

WHAT EVIDENCE FOR EVOLUTION DOES GENETICS PROVIDE?

Answer 38

- closely related orgs have more similarities in their DNA - explains the source of variation that is needed for evolution - shows how changes in the geno/pheno are transferred through generations

Question 39

OTHER FORMS OF EVIDENCE

Answer 39

- comparative biochemistry - vestigial organs - comparative embryology

Question 40

NATURAL SELECTION PROCESS

Answer 40

- large number... - variation - some have favorable... - change in environment - dying out, survival - reproduce - higher proportion - may lead to new species...

Question 41

PUNCTUATED EQUILIBRIUM EXPLANATION

Answer 41

- these species were in equil until sudden rapid changes interrupted their existence. they either failed to adapt and became extinct, or rapidly experienced many favorable mutations that enabled them to adapt to the new env. these rapid adaptations in order to survive accelerated evol and lead to speciation

Question 42

GRADUALISM

Answer 42

a slow gradual change in a species

Question 43

WHAT DOES PUNCTUATED EQUILIBRIUM EXPLAIN

Answer 43

explains how changes leading to speciation may occur very rapidly over short tme and explains the long periods in fossil records where species remain unchanged