Evolution - DP1 - Unit 1

Question 1

Homologous structures

Answer 1

Similar physical features in organisms that share a common ancestor, but the features serve completely different functions.

Question 2

Analogous structures

Answer 2

Biological structures having similar or corresponding functions but not from the same evolutionary origin

Question 3

Divergent evolution

Answer 3

What occurs when two groups of the same species evolve different traits within those groups in order to accommodate for differing environmental and social pressures.

Question 4

Convergent evolution

Answer 4

The process by which two species develop similar features despite not sharing a recent common ancestor.

Question 5

Adaptive radiation

Answer 5

The process by which many species originate from one species in an area and radiate to different species.
Example: Hawaiian honeycreepers

Question 6

Ecological niches

Answer 6

The position of a species within an ecosystem or community and its interrelationships with both bitoic and abiotic factors.

Question 7

Hybridisation

Answer 7

The act or process of mating organisms of different varieties or species to create a hybrid.

Question 8

Speciation

Answer 8

Process by which new species arise; involves the splitting of one ancesteral species into two or more descendent species which are genetically different from each and can no longer interbreed.

Question 9

Reproductive isolation

Answer 9

the inability of a species to breed successfully with related soecies due to geographical, behavioral, physiological, or genetic barriers or differences.

Question 10

Differential selection

Answer 10

The process of natural selection in which certain traits or variation within a population provide a selective advantage, leading to their increased frequency in generations, while other traits decrease in frequency or may be eliminated.

Question 11

Allopatric speciation

Answer 11

evolution of one or more new species from an ancesteral species due to geographical barrier.

Question 12

Sympatric speciation

Answer 12

evolution of one or more new species from an ancesteral species while living in the same geographical area.

Question 13

Intraspecific breeding

Answer 13

sexual reproduction within the same species

Question 14

geographical isolation

Answer 14

seperation of species by natural or human-made physical barriers.

Question 15

temporal isolation

Answer 15

a result of differences in the timing of the reproductive cycle like mating or gamete production.

Question 16

behavioural isolation

Answer 16

the presence or abscense of a specific behaviour that prevents reproduction.

Question 17

Polyploidy

Answer 17

When a diploid cell or organism acquires one or more additional set of chromosomes. It is a consequence of the duplication of chromosomes in a cell without subsequent cell division, resulting in whole-genome duplication.

Question 18

Allopolyploidy

Answer 18

A special case of polyploidy It is when a hybrid and has multpile chromosome sets that are derived from the different parental species. It can result in adbrupt speciation due to the hybrid not being able to mate with neither parent species.

Question 19

Organism

Answer 19

Any biological system that functions as an individual life form.

Question 20

Population

Answer 20

A group of organisms of the same species living in the same area at the same time.

Question 21

Community

Answer 21

Two or more populations of different species living in the same area.

Question 22

Discrete variation

Answer 22

Qualitative categories - bar graph

Question 23

Continous variation

Answer 23

Quantiative categories - histogram

Question 24

Species

Answer 24

Group of organisms that can successfully interbreed and produce fertile offspring.

Question 25

Genome

Answer 25

A complete set of genetic material in an organism.

Question 26

Gene

Answer 26

A specific segment of DNA that contains the intstructions for making a particular protein or functional RNA molecule.

Question 27

Allele

Answer 27

One or more alternative forms of a gene that occupy the same position on a chromosome.

Question 28

DNA barcodes

Answer 28

Short sections of DNA from one gene, or at most several genes, which are distinctive enough to identify a species.

Question 29

Environmental DNA

Answer 29

Organismal DNA that can be found in the abiotic factors of the environment.
Applications of DNA barcoding using environmental DNA: invasive species detection, ecosystem health monitoring, biodiversity assesment, etc.

Question 30

Evolution

Answer 30

A gradual, long-term process that involves changes in the genetic composition of populations of living organisms over successive generations. (”changes in the heritable characteristics”)

Question 31

Vestigial structures

Answer 31

Features of an organism that are considered to have lost much or all of their original function through evolution.

Question 32

Selective breeding

Answer 32

A process in which humans intentionally choose an mate individual organisms with specific desirable traits or characteristics to produce offspring with those traits.

Question 33

Natural selection

Answer 33

The process by which organisms with advantageous traits or characteristics have a higher likelihood of surviving and reproducing in a given environment, passing those beneficial traits to their offsprings. (VIDA)

Question 34

Biological variation

Answer 34

Diversity of traits and characteristics that exist within a population.

Question 35

Selective pressures

Answer 35

Factors that lead to differential survival or reproduction, which in turn cause a change in the geentic composition of a population.

Question 36

Density-dependent factors

Answer 36

Factors that affect the size of a population and depend on the density of the population.
Example: Availablity of food, predators, etc.

Question 37

Density-independent factors

Answer 37

Factors that affect the size of a population, irrespective of the population density.
Example: Natural disasters, pollution, oxygen levels, etc.

Question 38

Adaptation

Answer 38

Evolutionary process by which an organism or population acquires and develops traits, behavious, or physiological features that interests its fitness and enable it to better survive and reproduce in its specific ecological context.

Question 39

Fitness

Answer 39

The ability of an organism to successfully reproduce and pass on its genetic material to its offspring.

Question 40

Sexual selection

Answer 40

A special case of natural selection where the focus is on fincing a mate instead of survival.

Question 41

Intrasexual survival

Answer 41

Competition between individuals of one sex to mate with opposite sex.

Question 42

Intersexual selection

Answer 42

Indivdiauls of one sex choosing an inidividual of the opposite sex as a mate.

Question 43

Gene pool

Answer 43

Sum total of all the alleles of all the genes in a population.

Question 44

Allele frequency

Answer 44

The relative frequency of a particular allele in a population.

Question 45

Stabilizing selection

Answer 45

Selection pressures act to remove extreme varieties.
Example: Average human baby birth weight is better than low or high.

Question 46

Disruptive selection

Answer 46

Selection pressures act to remove intermediate variations, favoring both extremes.
Example: Mive living in an area with sandy beaches and dark-coloured rocks.

Question 47

Directional selection

Answer 47

Selection pressures favour one extreme form of a trait over all other.
Example: Giraffes with long necks.