Question 1

What is evolution?

Accepted Answer

The change in heritable characteristics over successive generations

(for example, the change in the size of a finch's beak is evolution; evolution doesn't always mean "better", just more adapted to the environment)

Question 2

What heritable characteristics?

Accepted Answer

Characteristics that can be passed down genetically

(blond hair, green eyes, etc.)

Question 3

What are genes?

Accepted Answer

A basic unit of heredity that carries information from one generation to the next

(formally: a sequence of nucleotides that contains instructions for the synthesis of RNA, which controls traits)

Question 4

What are alleles?

Accepted Answer

Any variation/form of a gene, acting as a trait

(a gene could code for eye color, and then example alleles would be brown eyes or blue eyes; pronounced: uh-leel)

Question 5

What is natural selection?

Accepted Answer

The process of organisms that are more adapted to their environment surviving and having more offspring

Question 6

Who was Charles Darwin?

Accepted Answer

A British naturalist who developed the theory of evolution

Question 7

Who was Jean-Baptise de Lamarck?

Accepted Answer

A French naturalist who developed an early theory of evolution before Darwin

Lamarck's theory was later proven wrong

Question 8

What is Lamarckism?

Accepted Answer

A (false) theory of evolution that physical changes that occurred during an organism's lifetime could be transmitted to children

(for example, a giraffe could stretch its neck and pass the longer neck to its children; this is false, do not write this on the exam)

Question 9

What is the difference between Lamarckian and Darwinian evolution?

Accepted Answer

Lamarck believed useful traits were acquired during an organism's life and passed to offspring

Darwin believed random traits were decided at birth and passed to offspring (if the organism survived long enough to reproduce)

Question 10

What is inheritance of acquired traits?

Accepted Answer

The incorrect belief that traits acquired during an organism's life will be passed to its offspring

This belief is the center of Lamarckism

(for example, if you lose a finger due to an accident this theory says your children may be born without a finger, which is obviously false)

Question 11

What is adaptation?

Accepted Answer

An evolutionary process where organisms adjust to their environment

(during ice ages, some species adapted by growing more fur through evolution)

Question 12

What is evolutionary fitness?

Accepted Answer

How well a species is able to survive and reproduce in its environment

Question 13

What are fossils?

Accepted Answer

Remains of an organism that are preserved in rock

Question 14

How do fossils help prove evolution?

Accepted Answer

They show that life on Earth has changed over time

(more recent fossils are more similar to modern life than earlier fossils)

Question 15

What is paleontology?

Accepted Answer

Branch of science that studies fossils

Question 16

What is comparative anatomy?

Accepted Answer

Studying similarities and differences in the anatomy of different species

Question 17

What are homologous structures?

Accepted Answer

Similar organ/skeletal structures in different species, that suggest a connection to a common ancestor

Question 18

What are analogous structures?

Accepted Answer

Similar structures in unrelated species

(wings in bats and birds)

Question 19

How do homologous structures help prove evolution?

Accepted Answer

Homologous structures indicate that a shared common ancestor split into multiple species

Question 20

How does DNA evidence/Molecular biology help prove evolution?

Accepted Answer

Many organisms that look very different are related at the genetic level

Demonstrates that they descended from a common ancestor

Question 21

What is biogeography?

Accepted Answer

The study of how animals and plants are distributed in an environment

Question 22

How does biogeography help prove evolution?

Accepted Answer

Species that are isolated on islands often evolve differently than species around them

Species on different continents that have similar features often have a common ancestor that was split due to plate-tectonics

Question 23

What is a common ancestor?

Accepted Answer

A species that two or more new species are evolved from

(chimps and humans share a common ancestor that lived around 6-7 million years ago)

Question 24

What are cladograms?

Accepted Answer

Branching charts built from fossil and molecular records that show relations between organisms

Every split is a common ancestor

Question 25

What is the main difference between phylogenetic trees and cladograms?

Accepted Answer

Phylogenetic trees generally show the timeline of how long evolution took

Cladograms usually do not include extinct species, while phylogenetic trees do

Phylogenetic tree:

Cladogram:

Question 26

What is an out-group in cladograms?

Accepted Answer

The species in a cladogram that is the least related to the other species

Question 27

What is parsimony in evolutionary trees?

Accepted Answer

The concept of choosing the simplest tree to fit the given evidence

(assume the tree that requires the fewest evolutionary changes is correct)

Question 28

What are vestigial organs/structures?

Accepted Answer

Structures that have lost their use in a species

They are inherited from a common ancestor that had a use for the structure

(your tailbone is a vestigial structure)

Question 29

How do vestigial organs/structures help prove evolution?

Accepted Answer

Provide evidence that an organism evolved to no longer need the structure

Question 30

What are transitional species?

Accepted Answer

A species that is intermediate between two different species

Question 31

How do transitional species help prove evolution?

Accepted Answer

They provide evidence that a species gradually evolved into a new species

Question 32

What is a fossil record?

Accepted Answer

A group of fossils that are chronologically arranged to describe how a species changed over time

Question 33

What is a molecular record?

Accepted Answer

A record describing how a species' DNA changed over time

Question 34

What is a molecular clock?

Accepted Answer

A technique used to deduce when two or more life forms diverged

(it does this by using the mutation rate of biomolecules)

Question 35

What is genetic variability?

Accepted Answer

Small and random genetic variation in organisms of the same species

(some humans have blue eyes, some have brown, some have green, etc.)

Question 36

What is a gene pool?

Accepted Answer

The set of all possible variations (alleles) of genes in a population

Question 37

What is environmental pressure?

Accepted Answer

Factors that in the environment that cause species to either adapt or die-off

(if an organism needs berries to survive, it faces environmental pressure to adapt a way to get berries)

Question 38

What is random mutation?

Accepted Answer

Random errors when copying DNA, that leads to new features

(mutations can be harmful, beneficial, or neither)

Question 39

What is sexual selection?

Accepted Answer

Natural selection that occurs due to the preference of the other sex

(large male peacock tails are dangerous to the peacock, but as female peacocks find large tails attractive so the tails develop)

Question 40

What is genetic drift?

Accepted Answer

The change in the genetics of a population due to random events

(unlike natural selection where more evolutionarily-fit organisms pass on alleles, this happens randomly)

Question 41

What is the bottleneck-effect/founder-effect in evolution?

Accepted Answer

When the size of a population is severely reduced, the alleles in the lucky organisms that survive become more common

(this is an example of genetic drift)

Question 42

What is gene flow?

Accepted Answer

The transfer of alleles from one population to another

(occurs if individuals migrate between populations)

Question 43

What is reproductive isolation?

Accepted Answer

A physical barrier preventing two or more populations of the same species from breeding

Question 44

What is a long term effect of reproductive isolation?

Accepted Answer

Speciation

(the two groups split into different species, that are no longer able to breed with each other)

Question 45

What is speciation?

Accepted Answer

The process of forming a new species, in the course of evolution

Question 46

What is habitat isolation?

Accepted Answer

A form of reproductive isolation where populations are separated by preference for different habitats

(if one population likes swamps and the other likes grasslands, they will not breed because they do not like to go into each other's habitats)

Question 47

What is temporal isolation?

Accepted Answer

A form of reproductive isolation where different populations are ready to mate at different times of the year

Question 48

What is behavioral isolation?

Accepted Answer

A form of reproductive isolation, where populations won't breed with each other due to differences in behavior

(some populations have very specific mating calls, which other nearby populations won't recognize)

Question 49

What is mechanical isolation?

Accepted Answer

A form of reproductive isolation where mating is physically impossible

(the genitalia of the species don't match)

Question 50

What is spatial isolation?

Accepted Answer

A form of reproductive isolation where populations are too far apart to breed

Question 51

What is geographical isolation?

Accepted Answer

A form of reproductive isolation where organisms are nearby but separated by a geographical feature

(such as mountains or water)

Question 52

What is gametic isolation?

Accepted Answer

A form of reproductive isolation where gametes (sperm and egg) are unable to fuse and fertilize

(may happen if the female immune system recognizes sperm as foreign and attacks it)

Question 53

What is divergent evolution?

Accepted Answer

The process of groups from the same common ancestor accumulating differences until they become a new species

Question 54

What is punctuated equilibrium?

Accepted Answer

The hypothesis that evolution occurs in small bursts after long periods of little change

(opposite of gradualism)

Question 55

What is gradualism?

Accepted Answer

The hypothesis that evolution occurs in tiny steps over a long period of time

(opposite of punctuated equilibrium)

Question 56

What is adaptive radiation?

Accepted Answer

The process of a group diversifying to fit a bunch of new niches

Question 57

What is a pre-zygotic barrier?

Accepted Answer

A class of reproductive isolation that occurs before fertilization

(prevents the organisms from forming a fertilized egg; this includes things such as geographic isolation)

Question 58

What is a post-zygotic barrier?

Accepted Answer

The inability of a hybrid organism to produce offspring

(horses and donkeys can mate to create mules, but mules are unable to reproduce)

Question 59

What is convergent evolution?

Accepted Answer

The process of unrelated species evolving similar traits

Due to similar selective pressures

Question 60

What is allopatric speciation?

Accepted Answer

A type of speciation that occurs when a population is physically separated by the rest of the species by a barrier

Question 61

What is sympatric speciation?

Accepted Answer

A type of speciation that occurs without a geographic barrier

(common in plants; occurs due to some event that prevents the offspring from being able to mate with the rest of the species, such as polyplody)

Question 62

What is artificial selection?

Accepted Answer

The process of humans breeding certain plant/animal species to selectively develop a certain trait

(breeding sweeter berries, which causes sweet berries to become more common)

Question 63

What are human-caused changes in species?

Accepted Answer

Evolutionary changes in a species, due to human interference

(pigeons adapting to live in cities and eat out of trash cans, due to human civilization)

Question 64

What is a phenotype?

Accepted Answer

The set of observable characteristics about an organism

Caused by the organism's genotype

(you can see someone's hair color with your eyes, but you can't see the genes that caused it)

Unit 7: Natural Selection, AP Biology Flashcards