Evolution lab practical 1

Question 1

Evolution

Answer 1

Descent with modification. Involves changes in allele frequencies over time

Question 2

Natural selection

Answer 2

the selection for those phenotypes that are better adapted with the result that such phenotypes contribute more surviving offspring to the population than other phenotypes

Question 3

When does evolution occur (5 factors)

Answer 3

1. Mutation: produce variation in the gene pool
2. Gene flow: frequency of genes in the gene pool may change due to immigration or emigration
3. Natural selection: impact of the environment on the frequency of alleles
4. Genetic drift: frequency of alleles in the gene pool may change by pure chance
5. Nonrandom mating: if there is a mating preference in the population, the frequency of alleles in that population will change

Question 4

Dichotomous key

Answer 4

A tool that allows the user to determine the identity of items in the natural world. They consist of a series of choices that lead to the correct name of the given item

Question 5

Cladogram

Answer 5

A branching diagram showing relationship between a number of species. They focus on identifying common ancestry of related groups

Question 6

Name the six kingdoms and give an example of each

Answer 6

Plants (trees), animals (human), protists (protozoa, algae), fungi (yeast), archeabacteria (crenarchaeota), eubacteria (e. coli)

Question 7

How are scientific names derived

Answer 7

The first word is the genus the species belongs to. The second word is specific to the organism and is called the species epithet. The words are greek or latin

Question 8

Castle-Hardy-Weinberg law

Answer 8

simple mathematical expression that establishes a point of reference in evaluating genetic changes in a population

Question 9

Castle-Hardy-Weinberg formulas

Answer 9

p+q=1

p^2+2pq+q^2=1

Question 10

Castle-Hardy-Weinberg conditions

Answer 10

1. Mutations do not occur
2. The population size is large
3. The population is isolated from other populations of the same species (no immigration or emigration occurs)
4. No selection takes place (the genotypes are equally viable and fertile)
5. Mating is random

Question 11

Taxonomy

Answer 11

The study of the principles, procedures, and rules of scientific classification and the naming of organisms
(Science of classifying organisms)

Question 12

Phylogenetics

Answer 12

What cladistics is sometimes referred to because cladograms are generated from similarities in the molecular structure of organisms

Question 13

Theory of evolution

Answer 13

postulates that the modern species of organisms are descendants of a common ancestor and that their present characteristics have come from genetic variation and natural selection

Question 14

Species

Answer 14

Members of a species share common genes and can breed to produce fertile offspring

Question 15

Fossil

Answer 15

A preserved remnant or impression of an organism

Question 16

Fossil record

Answer 16

the sequence of fossils from the oldest to the most recent

Question 17

Homologous structures

Answer 17

Structures who’s similarity is due to descent from a common ancestor

Question 18

Divergent evolution

Answer 18

What homologous structures result from as related organisms expand into new environments

Question 19

Analogous structures

Answer 19

Have similar functions in unrelated organisms (ex: butterfly and bat wings)

Question 20

Convergent evolution

Answer 20

What analogous structures result from when unrelated organisms are objected to similar environmental pressures

Question 21

Timeline of human evolution in order

Answer 21

1. Ardipithecus ramidus
2. Australopithecus afarensis
3. A. africanus
4. A. boisei
5. A. robustus
6. A. habilis
7. Homo erectus
8. Homo neanderthalensis
9. Homo sapien

Question 22

When were Hominids around in Africa

Answer 22

8 to 5 mya

Question 23

When did the earliest hominid (a. ramidus) live

Answer 23

4.4 mya

Question 24

When did the oldest austra…. live (a. anamensis)

Answer 24

4 mya

Question 25

What was pangea

Answer 25

Pangea was the super continent during the Permian period

Question 26

How does pangea relate to the fossil record

Answer 26

Fossils of the same organisms were found on two separate continents, suggesting that they were connected when those organisms roamed the earth. When the continents separated, organisms evolved to their environments. Today, organisms on separate continents have features that show they share a common ancestor

Question 27

Unity in evolution

Answer 27

We are united through common ancestry

Question 28

Diversity in evolution

Answer 28

We are diverse because of our physiology, morphology, etc. due to evolution over time

Question 29

Evidence of common ancestor in embryos

Answer 29

Early embryos of different organisms look nearly identical. All possess pharyngeal pouches, aortic arches and post anal tail

Question 30

Evolution postulates

Answer 30

1. Modern species of organisms are descendants of a common ancestor 2. Their present characteristics have come from genetic variation and natural selection

Question 31

Antibodies

Answer 31

proteins that protect against forgein proteins that enter the body

Question 32

Antigens

Answer 32

foreign proteins that enter the body

Question 33

Out-of-africa hypothesis

Answer 33

proposes that early H. sapiens evolved from H. erectus in Africa about 150,000 years ago and migrated to other parts of the world

Question 34

Multiregional hypothesis

Answer 34

Holds that localized populations of early H. sapiens evolved independently from H. erectus in several regions of the world

Question 35

What general trend is evident in organismic diversity

Answer 35

As time went on, diversity increased. This is because many new species evolved from the original ancestors

Question 36

What general trend is evident in organismic complexity

Answer 36

As time went on, complexity increased. This is because over time, organisms developed adaptations to better survive in their environments

Question 37

Are there exceptions to the trend of diversity and complexity increasing as time goes on

Answer 37

Yes. Today there are still simple organisms that lived in earth's early years that survived mass extinctions

Question 38

How did cyanobacteria prepare the way for the origin of aerobic respiration

Answer 38

They undergo photosynthesis and release oxygen into the atmosphere

Question 39

Considering the drifting of continents, how do you explain the presence of fossils or tropical organisms in Canada

Answer 39

Canada was once in the tropics so tropical organisms once flourished there

Question 40

Considering the drifting of the continents, how do you explain the absence of marsupials and the presence of native placental mammals in Australia

Answer 40

Australia was probably one of the first continents to break off of Pangea

Question 41

For a group of organisms to radiate, there must be niches (ways of making a living) available for the taking. What made niches available for the radiation of: 1) mammals: 2) amphibians:

Answer 41

1) Mammals: the extinction of dinosaurs (loss of competitiors) 2) Amphibians: they didnt have much competition and the closeness of the continents to eachother allowed them to spread out

Question 42

Extinction is a common occurrance in the fossil record. Why do you think species become extinct

Answer 42

They become extinct because they are unable to adapt

Question 43

All organisms possess ATP, RNA, and DNA. What can you infer from this

Answer 43

There is a common ancestor

Question 44

Would you expect plasma proteins of closely related species or distantly related species to have the greater similarity?

Answer 44

The more closely related they are, the more similar the protein structure

Question 45

If you want to identify the various species of birds in you backyard, what sources could you use to fins their names

Answer 45

A dichotomous key could be used. By observing the characteristics of each species, you could use the dichotomous key to narrow down the possibilities

Question 46

How does the cladistics system of taxonomy differ from the hierarchial system of classification

Answer 46

Cladograms show relationships between organisms by trying to identify a common ancestor. A heirarchial system of classification begins broad and organisms become more similar with each level. Sometimes, cladograms do not align with the actual evolutionary past. They are only hypothesis until the genetic data becomes available.

Question 47

Evidence of evolution from embryos

Answer 47

They all posess pharyngeal pouches, aortic arches, post anal tail . All veterbrates have similar genes directing early embryonic development (common ancestor)

Question 48

Evidence of evolution from vertabrate anatomy

Answer 48

Forelimbs in each organism exhibit similar basic body plan (common ancestor). Bones specialized for particular functions in each organism

Question 49

Does evolution of a body part produce the single best structural design or a functional modification of the basic structure available?

Answer 49

No. Depending on the environmental situation, it will evolve differently.