Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIEB 150 > Final > Flashcards

Final Flashcards

(49 cards)

Start Studying
1
Q

What is Phylogenetics?
3 points

A

Study of evolutionary relationships between organisms.

Explores common ancestors and the divergence of species.

Essential for understanding evolutionary questions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is a root

A

most ancient lineage in the tree

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is a node

A

Represents common ancestors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is a terminal node?

A

Current (extant) species.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is an internal node?

A

Hypothetical ancestors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what does a branch show?

A

Show evolutionary paths.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the 2 types of trees?

A

rooted tree = shows direction + time of evol

unrooted tree = no ancestor is specified; relationship w/o directionality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is a clade or monophyletic group?

A

Group including an ancestor and all its descendants.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are the three types of clade classification?

A

Monophyletic: Includes all descendants of a single common ancestor

Paraphyletic: Includes some, but not all, descendants of a common ancestor

Polyphyletic: Group of species w/o an immediate common ancestor, often due to convergent evolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

define Homology and Analogy

A

Homology: Traits shared due to a common ancestor

Analogy: Traits w/ similar functions but evolved independently

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

define parsimony

A

Assumes the simplest evolutionary path is most likely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are three challenges in constructing a phylogenetic tree? 3 total

A

Homoplasy: Similar traits from independent evolution.

Gene Trees vs. Species Trees: Gene evolution can differ from species evolution.

Incomplete Lineage Sorting: Some ancestral alleles are not evenly distributed among descendant species.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are in phylogenetic trees used for? 3 total

A

Classification: Organizing biodiversity into monophyletic groups.

Understanding Evolution: Tracing traits and diversification.

Conservation: Prioritizing species with unique evolutionary histories.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what contributes to the challenges in building a tree? 2 points

A

Horizontal Gene Transfer: Gene flow between unrelated lineages (common in microbes).

Rapid Speciation: Causes difficulty in resolving relationships due to limited time for genetic divergence.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how can you overcome the challenges in building a tree?

A

Using Genomes: Modern phylogenetics often analyzes entire genomes for accuracy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the purpose of QLT?

A

Identifies genetic regions (QTLs) associated w/ phenotypic traits.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the process of QLT? 2 points

A
  1. Cross 2 populations W/ DIFF traits (e.g., color)
  2. Produce recombinants to observe associations between genetic markers and phenotypes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the limitations in QLT?

A

Requires controlled crosses, unsuitable for species like humans or endangered animals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the purpose of GWAS?

A

identifies genetic loci linked to traits or diseases in natural populations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is the process of GWAS?

Study These Flashcards
A
  1. Compare allele frequencies between cases (e.g., disease) and controls (healthy individuals).
  2. Use statistical associations to pinpoint relevant loci.
21
Q

what is the advantage of GWAS?

Study These Flashcards
A

No need for experimental crosses; applicable to humans and wildlife.

22
Q

Define Fixation Index (FST)? what does an FST of 0 mean? what about 1?

Study These Flashcards
A

Definition: Measures genetic differentiation between pops to identify loci driving pop differences

0 = no differentiation; same
1 = complete differentiation; diff

23
Q

Challenges in Linking Genotypes to Phenotypes? 2

Study These Flashcards
A

Polygenic Traits: Many genes influence traits, making it hard to detect associations.

Small Effect Sizes: Traits influenced by multiple genes require large sample sizes + precise measurement

24
Q

define evolution. what does it require?

Study These Flashcards
A

A change in the frequency of heritable traits across generations.

Requires mutation, drift, selection, or migration.

25
what is uniformitarianism by Hutton & Lyell?
Gradual geological changes over millions of years
26
what did Cuvier demonstrate? what did he propose?
Demonstrated extinction via fossils. Proposed catastrophism: Sudden events (e.g., floods) explain geological changes.
27
what 2 ideas did Darwin propose?
Descent with Modification: All species descend from common ancestors. Over time, species accumulate differences, leading to biodiversity. Natural Selection: Differential survival + reproduction of individuals based on trait advantages. Results in adaptations suited to the environment.
28
what are Darwin’s Four Postulates for Natural Selection?
1. Variation exists within populations. 2. Variation is heritable. 3. More offspring are produced than can survive. 4. Survival and reproduction are non-random and depend on traits.
29
What is Dawkins's ideas on evol?
Evolution occurs through descent w/ modification + natural selection. Key Points: All life shares a common ancestor. Traits change over time due to environmental pressures. Natural selection = survival and reproduction of the fittest phenotypes.
30
what does each evolutionary force change via what processes?
Natural Selection: Non-random process; leads to adaptations. Genetic Drift: Random changes in allele frequencies. Gene Flow: Migration introduces genetic variation. Mutation: Creates new alleles.
31
can evolution occur quickly?
YES
32
define Microevolution. what are the mechs that drive microevol?
Small changes within a species over generations. Mechanisms: mutation, selection, gene flow, genetic drift
33
define macroevolution. what are the mechs that drive macroevol
Large-scale changes leading to new species over long periods. mech: Nast sel
34
define transitional fossils
Fossils showing traits of both ancestors and descendants. Show intermediate features between groups Indicate gradual evolutionary changes.
35
what is deep time concept?
earth's age (4.5 billion years) provides a vast timeline for evolution
36
Evidence for Darwins 4 Postulates?
Variation: Seen in traits like beetle spots or stickleback armor plates. Heritability: Traits like height in humans can predict offspring traits based on parental averages. Struggle for Existence: Resource limitations prevent infinite population growth (e.g., pheasants on an island). Non-Random Reproduction: Traits like peacock eye spots affect mate selection.
37
are muts a source of variation? how?
yes. Mutations create genetic variation, the raw material for evolution.
38
define gremlin muts? somatic muts? point muts? synonymous muts? Nonsynonymous muts?
Germline Mutations: Passed to offspring and drive evolution. Somatic Mutations: Affect individual cells but are not inherited. Point Mutations: Change a single base pair; effects depend on whether they alter protein function. Synonymous: No change in amino acids; neutral. Nonsynonymous: Changes amino acids; can affect phenotype and adaptation.
39
Insertions/Deletions (Indels) cause...
frameshifts unless it occurs in multiple of threes
40
Inversions impact...
recombination and fertility.
41
Duplications enable new functions such as...
Subfunctionalization: Specialization of duplicated genes for different functions. Neofunctionalization: One copy evolves a new function while the other maintains the original.
42
Chromosome Fusion reduces...
chromo #
43
Polyploidy leads to rapid speciation bc of...
Entire genome duplication
44
Gene duplications enable evolutionary innovation by...
providing raw material for adaptation
45
Mutations occur BLANK and are the basis for BLANK
randomly; evolutionary change
46
larger organisms often have... Random mutations become visible under selection pressures, such as antibiotics or viruses.
higher rates per genome.
47
Most mutations are BLANK BLANK muts are rare but significant
neutral or harmful; beneficial
48
True or false: Pre-existing genetic variation often provides resistance to new environmental pressures
TRUE
49
True or false: Muts are more likely to disrupt than improve functions.
ture

BIEB 150 (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions