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GENETICS Flashcards

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1
Q

What are alleles?

A

Alternative forms of a gene located at the same genetic locus on homologous chromosomes

Alleles are crucial for understanding genetic variation and inheritance.

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2
Q

What type of alleles express their traits in heterozygotes?

A

Dominant alleles

Recessive alleles are expressed only in homozygotes.

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3
Q

In a population, multiple alleles for a gene may exist, contributing to __________.

A

genetic diversity

This variation is important for the adaptability of populations.

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4
Q

Name the three types of allelic interactions.

A
  • Dominance
  • Codominance
  • Incomplete dominance

These interactions describe how different alleles affect phenotype expression.

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5
Q

How do alleles influence an organism’s phenotype?

A

By determining the traits expressed

The phenotype is the observable characteristics of an organism.

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6
Q

What determines an individual’s genotype and phenotype?

A

The combination of alleles inherited from parents

Genotype refers to the genetic makeup, while phenotype refers to the observable traits.

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7
Q

True or false: Alleles are fundamental to understanding genetic variation and inheritance.

A

TRUE

They play a key role in the diversity of traits within populations.

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8
Q

What are concordant alleles referred to as?

A

homozygous

Concordant alleles include examples like AA and aa.

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9
Q

What are discordant alleles referred to as?

A

heterozygous

Discordant alleles include examples like Aa.

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10
Q

When are dominant alleles phenotypically expressed?

A

Whenever present

Dominant alleles mask the expression of recessive alleles.

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11
Q

When are recessive alleles phenotypically expressed?

A

When dominant alleles are absent

Recessive traits only show when no dominant alleles are present.

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12
Q

What is complete dominance?

A

One allele completely masks the expression of the other

Results in a clear phenotypic distinction between dominant and recessive traits.

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13
Q

Provide an example of complete dominance.

A

Flower color in Mendel’s pea plants (PP or Pp for purple, pp for white)

This illustrates how dominant traits can mask recessive ones.

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14
Q

What is incomplete dominance?

A

Neither allele is completely dominant, and the heterozygote shows an intermediate phenotype

Results in a blending of traits.

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15
Q

Provide an example of incomplete dominance.

A

Snapdragons’ flower color (W for pink from red and white alleles)

This shows how traits can blend in heterozygotes.

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16
Q

What is co-dominance?

A

Both alleles are independently expressed in the heterozygote

Results in a phenotype that reflects contributions from both alleles.

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17
Q

Provide an example of co-dominance.

A

ABO blood group system (IAIA or IAi for type A, IBIB or IBi for type B, IAIB for type AB)

This illustrates how both alleles can be expressed simultaneously.

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18
Q

What is epistasis?

A

The ability of one gene to influence the expression of another

It describes the interaction of genes that are not alleles.

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19
Q

Define wild-type.

A

“Normal” allele or phenotype for an organism

This typically corresponds to the form of the organism that is most commonly seen in the wild.

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20
Q

What does phenotype variability refer to?

A

Variation in phenotype expression based on a gene’s penetrance and expressivity

It indicates how genetic traits can manifest differently among individuals.

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21
Q

What is penetrance?

A

The proportion of people with a particular genetic variant who exhibit signs and symptoms of a genetic disorder

Example: Many patients with BRCA1/2 never develop breast cancer.

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22
Q

What is expressivity?

A

The varying phenotype that may result in individuals from the same genetic condition

Example: Individuals with mutations in FBN1 can have few symptoms or severe cardiovascular abnormalities.

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23
Q

True or false: Epistasis involves the interaction of alleles.

A

FALSE

Epistasis refers to the interaction of genes that are not alleles.

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24
Q

Give an example of epistatic relationships.

A

Suppression of the effect of one gene by another

This illustrates how one gene can mask the expression of another.

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25
What is an example of a **wild-type** organism?
A brown mouse ## Footnote This represents the most commonly seen phenotype in the wild.
26
Fill in the blank: **Variable penetrance** refers to the _______ of individuals with a genetic variant showing symptoms.
proportion ## Footnote It highlights that not all individuals with a genetic variant will exhibit the associated disorder.
27
Fill in the blank: **Variable expressivity** refers to the _______ of symptoms among individuals with the same genetic condition.
variation ## Footnote This indicates that individuals can experience different severities or types of symptoms.
28
What is **Genetic Diversity**?
The variety of genetic characteristics within a species ## Footnote It is essential for the adaptability and survival of species.
29
What does the **Law of Segregation** state?
* Alleles segregate during gamete formation * Each gamete carries only one allele for each trait ## Footnote Example: In a monohybrid cross (e.g., Aa x Aa), alleles for a trait segregate, resulting in a 1:2:1 genotypic ratio (AA:Aa:aa).
30
In a monohybrid cross (e.g., Aa x Aa), what is the resulting **genotypic ratio**?
1:2:1 ## Footnote This ratio represents the distribution of genotypes (AA:Aa:aa) among the offspring.
31
What is the **Law of Independent Assortment**?
* Genes located on different chromosomes assort independently during gamete formation ## Footnote Example: In a dihybrid cross (e.g., AaBb × AaBb), alleles for different traits assort independently, producing a 9:3:3:1 phenotypic ratio.
32
In a dihybrid cross (e.g., AaBb × AaBb), what is the resulting **phenotypic ratio**?
9:3:3:1 ## Footnote This ratio reflects the independent assortment of two traits.
33
What does the **Law of Dominance** state?
* Some alleles are dominant and express their traits in heterozygotes * Others are recessive ## Footnote Example: In a monohybrid cross (e.g., Aa x Aa), the dominant allele (A) masks the expression of the recessive allele (a) in the phenotype, resulting in a 3:1 phenotypic ratio.
34
In a monohybrid cross (e.g., Aa x Aa), what is the resulting **phenotypic ratio**?
3:1 ## Footnote This ratio indicates the dominance of the dominant allele over the recessive allele in the phenotype.
35
What are the **antibodies in plasma** for **GROUP A**?
Anti-B ## Footnote GROUP A has A Antigen on red blood cells.
36
What are the **antigens on red blood cells** for **GROUP B**?
B Antigen ## Footnote GROUP B has Anti-A antibodies in plasma.
37
What are the **antibodies in plasma** for **GROUP AB**?
None ## Footnote GROUP AB has A and B Antigens on red blood cells.
38
What are the **antibodies in plasma** for **GROUP O**?
Anti-A and Anti-B ## Footnote GROUP O has no antigens on red blood cells.
39
What is the **antigen** present on red blood cells for **GROUP A**?
A Antigen ## Footnote GROUP A has Anti-B antibodies in plasma.
40
What is the **antigen** present on red blood cells for **GROUP B**?
B Antigen ## Footnote GROUP B has Anti-A antibodies in plasma.
41
What are the **antigens** present on red blood cells for **GROUP AB**?
A and B Antigens ## Footnote GROUP AB has no antibodies in plasma.
42
What are the **antigens** present on red blood cells for **GROUP O**?
None ## Footnote GROUP O has Anti-A and Anti-B antibodies in plasma.
43
What does **genetic diversity** refer to?
The total number of different genes in a population ## Footnote It is a measure of the variety of genes within a given population.
44
What is the **gene pool**?
All genes/alleles in a population at a given time ## Footnote A larger gene pool indicates increased genetic diversity.
45
Increased **gene pool** leads to what outcomes?
* Increased genetic diversity * Increased fitness ## Footnote A diverse gene pool can enhance a population's ability to adapt and survive.
46
Define **hybridization**.
Process of two complementary, single-stranded DNA or RNA combining to produce a double-stranded molecule ## Footnote It is used for interbreeding between individuals of genetically distinct populations.
47
What is the effect of increased parent genetic diversity on offspring?
Increased offspring viability ## Footnote Higher genetic diversity can lead to healthier and more resilient offspring.
48
List the **four main mechanisms** that introduce genetic variability.
* Genetic errors (mutations) * Random mating * Random fertilization * Genetic recombination ## Footnote These processes contribute significantly to genetic variability during reproduction.
49
What is the role of **independent assortment** in genetic variability?
It contributes to genetic variability during meiosis ## Footnote Independent assortment ensures that alleles segregate independently during gamete formation.
50
What is **meiosis**?
Cell division process that produces gametes with half the chromosome number of the parent cell ## Footnote Meiosis results in four non-identical haploid cells.
51
What is the outcome of meiosis in terms of chromosome number?
Results in four non-identical haploid cells (gametes) ## Footnote Each gamete contains half the chromosome number of the original cell.
52
How does meiosis ensure **genetic diversity**?
By introducing variation through crossing-over and random assortment of chromosomes ## Footnote These processes create new combinations of genes in the gametes.
53
What is the difference in chromosome number between daughter cells after **mitosis** and **meiosis**?
Mitosis: 46 chromosomes; Meiosis: 23 chromosomes ## Footnote Mitosis produces identical daughter cells, while meiosis produces gametes with half the chromosome number.
54
What occurs during **Prophase I** of meiosis?
* Chromosomes condense * Homologous pairs synapse * Crossing-over occurs ## Footnote Prophase I is a critical stage where genetic recombination takes place.
55
During **Metaphase I**, what is the arrangement of chromosomes?
* Homologous pairs align at the cell equator ## Footnote This alignment is crucial for the proper segregation of chromosomes.
56
What happens in **Anaphase I** of meiosis?
* Homologous pairs separate and move to opposite poles ## Footnote This separation reduces the chromosome number by half.
57
What is the outcome of **Telophase I**?
* Chromosomes reach poles * Cell divides into two haploid cells ## Footnote Each resulting cell contains half the original chromosome number.
58
What occurs during **Prophase II**?
* Chromosomes condense in haploid cells ## Footnote This prepares the chromosomes for alignment in the next phase.
59
What happens during **Metaphase II**?
* Chromosomes align along the cell equator ## Footnote This is similar to Metaphase in mitosis.
60
What is the result of **Anaphase II**?
* Chromatids separate ## Footnote This separation leads to the formation of individual chromosomes.
61
What occurs during **Telophase II** and **Cytokinesis**?
* Cells divide, producing four non-identical haploid cells ## Footnote This final step completes meiosis, resulting in gametes.
62
What is the **parent cell** in mitosis?
2n ## Footnote The parent cell undergoes mitosis to produce two genetically identical daughter cells.
63
In **prophase** of mitosis, what is notable about homologous chromosomes?
No pairing of homologous chromosomes ## Footnote This distinguishes mitosis from meiosis.
64
During **metaphase** of mitosis, where do individual chromosomes align?
At the equatorial plate ## Footnote This alignment is crucial for proper chromosome separation.
65
What happens during **anaphase** of mitosis?
* Centromeres separate * Sister chromatids separate, becoming daughter chromosomes ## Footnote This leads to the formation of two daughter cells.
66
What are the **products** of mitosis?
Two daughter cells (each 2n) ## Footnote These cells are genetically identical to the parent cell.
67
What is the **parent cell** in meiosis?
2n ## Footnote The parent cell undergoes meiosis to produce four genetically distinct daughter cells.
68
In **prophase 1** of meiosis, what is notable about homologous chromosomes?
No pairing of homologous chromosomes ## Footnote This is different from later stages in meiosis.
69
During **metaphase 1** of meiosis, where do individual chromosomes align?
At the equatorial plate ## Footnote This alignment is essential for the segregation of homologous chromosomes.
70
What occurs during **anaphase 1** of meiosis?
* Centromeres separate * Sister chromatids separate, becoming daughter chromosomes ## Footnote This leads to the segregation of homologous chromosomes.
71
What are the **products** of meiosis?
Four daughter cells (each n) ## Footnote These cells are haploid and genetically distinct.
72
What happens at the end of **telophase I** in meiosis?
The two homologs are segregated from one another ## Footnote This prepares the cells for meiosis II.
73
After **telophase I**, what occurs in the daughter cells?
Undergo meiosis II without an intervening DNA replication ## Footnote This is a key difference from mitosis.
74
What is the role of **meiosis** in terms of genetic diversity?
Generating diversity ## Footnote Meiosis produces genetically distinct daughter cells, unlike mitosis.
75
What is the **mechanism** of **independent assortment**?
Generates genetic variation by shuffling chromosomes and placing only one copy of each into the gamete ## Footnote This process ensures that alleles segregate independently during gamete formation.
76
In the example **AaBb**, how do the **A** and **B** alleles assort?
Independent of each other ## Footnote This illustrates the principle of independent assortment in genetics.
77
During which phase of **meiosis** does independent assortment occur?
Metaphase I ## Footnote Homologous chromosomes pair up along the metaphase line in random orientation.
78
What happens during **anaphase I** of meiosis related to independent assortment?
Homologous chromosomes are pulled apart ## Footnote This results in a 50/50 chance of where one homolog will go.
79
What is the process of **cell division** that results in two identical daughter cells?
Mitosis ## Footnote Mitosis involves one division and produces diploid (2n) daughter cells.
80
In **meiosis**, what is formed during the process that involves homologous chromosomes pairing and crossing over?
Tetrad formation ## Footnote Tetrads consist of paired homologous chromosomes.
81
What type of daughter cells are produced by **mitosis**?
Diploid (2n) daughter cells ## Footnote These daughter cells are identical to the parent cells.
82
How many divisions are involved in **meiosis**?
2 divisions involved ## Footnote Meiosis results in daughter cells that are different from the parent cells.
83
What is the total number of daughter cells produced by **meiosis**?
4 sperm cells or 1 egg (with polar bodies) ## Footnote Meiosis produces haploid (n) daughter cells.
84
What is the term for the daughter cells produced in **mitosis**?
Diploid Daughter cells identical to parent ## Footnote Mitosis results in two identical daughter cells.
85
What type of daughter cells are produced by **meiosis**?
Haploid (n) daughter cells ## Footnote These cells are genetically different from the parent cells.
86
In **mitosis**, how many daughter cells are produced?
2 daughter cells ## Footnote Mitosis involves one division.
87
In **meiosis**, what is the significance of tetrad formation?
Homologous chromosomes pairing and crossing over ## Footnote This process increases genetic diversity.
88
True or false: **Mitosis** results in daughter cells that are different from the parent cells.
FALSE ## Footnote Mitosis produces identical daughter cells.
89
What is the **first notable exception** to Mendelian genetics?
Linkage ## Footnote Linkage refers to genes that are near each other on the same chromosome being more likely to be inherited together, which breaks the law of independent assortment.
90
Define **pleiotropy** in the context of genetics.
Single gene may influence many genetic characteristics ## Footnote Pleiotropy illustrates how one gene can affect multiple traits.
91
What are **multiple allele traits**?
Single trait/characteristic may be influenced by many alleles ## Footnote This concept shows that a trait can be determined by more than two alleles.
92
What is **codominance**?
Breaks law of dominance ## Footnote In codominance, both alleles in a heterozygote are fully expressed, resulting in a phenotype that is neither dominant nor recessive.
93
What is **incomplete dominance**?
Breaks law of dominance ## Footnote Incomplete dominance occurs when the phenotype of a heterozygote is intermediate between the phenotypes of the two homozygotes.
94
What is **crossing over** in meiosis?
Random distribution of homologous chromosome pairs ## Footnote Results in genetic diversity as different combinations of alleles end up in gametes.
95
In a **dihybrid cross**, what do genes for different traits do?
Assort independently ## Footnote This generates various allele combinations.
96
What is a **chiasma**?
Point where paired chromosomes remain in contact during metaphase I ## Footnote Crossing over and exchange of genetic material occur between strands.
97
Define **synapsis**.
Pairing of homologous chromosomes during prophase I ## Footnote Involves alignment side by side, forming the synaptonemal complex.
98
What is the role of **synapsis** in meiosis?
Facilitates crossing over and exchange of genetic material ## Footnote Occurs between homologous chromosomes.
99
What are **sex-linked traits**?
Gene for characteristic is on the X chromosome ## Footnote All sex-linked alleles are carried on the X chromosome.
100
What does **XX** represent in sex determination?
Female ## Footnote This is part of the chromosomal basis of sex determination.
101
What does **XY** represent in sex determination?
Male ## Footnote This is part of the chromosomal basis of sex determination.
102
What is the function of the **Y chromosome** in mammals?
Determines male development ## Footnote Carries genes related to male-specific traits and fertility.
103
How is the **Y chromosome** inherited?
Passed from father to son ## Footnote Maintains paternal lineage.
104
What are **Y-linked disorders**?
Mutations on the Y chromosome may lead to conditions affecting male reproductive functions ## Footnote These disorders are specific to males due to Y chromosome inheritance.
105
Define **cytoplasmic inheritance**.
Inheritance of things other than genomic DNA ## Footnote Mitochondria and chloroplasts can replicate independent of nuclear DNA.
106
From whom are all cellular organelles, such as mitochondria, inherited?
Mother ## Footnote This is a key aspect of cytoplasmic inheritance.
107
What does the **Hardy-Weinberg Principle** describe?
Stable allele frequencies in a non-evolving population ## Footnote It serves as a baseline for understanding evolutionary forces and detecting deviations.
108
What is the **first formula** of the Hardy-Weinberg Principle?
p + q = 1 ## Footnote The percentage of each of the two alleles (p and q) must total 100%.
109
If p = 0.90, what is the value of q in the Hardy-Weinberg Principle?
0.10 ## Footnote This follows from the formula p + q = 1.
110
What is the **second formula** of the Hardy-Weinberg Principle?
p² + 2pq + q² = 1 ## Footnote Here, p' and q' are proportions of homozygous individuals, while 2pq represents heterozygous individuals.
111
List the **five assumptions** of the Hardy-Weinberg Principle.
* Large Population * No Migration * No Mutation * No Selection ## Footnote These assumptions ensure random mating and prevent genetic drift.
112
What does a **large population** assumption ensure in the Hardy-Weinberg Principle?
Random mating and prevents genetic drift ## Footnote This is crucial for maintaining stable allele frequencies.
113
True or false: The Hardy-Weinberg Principle assumes that **gene flow** between populations is present.
FALSE ## Footnote The principle assumes no migration, meaning gene flow is absent.
114
What does the **no mutation** assumption imply in the Hardy-Weinberg Principle?
Genetic material remains unchanged ## Footnote This is essential for maintaining allele frequencies over time.
115
What does the **no selection** assumption state in the Hardy-Weinberg Principle?
All genotypes have equal fitness ## Footnote This means that no genotype is favored over another in terms of survival and reproduction.
116
What mnemonic can be used to remember the assumptions of the Hardy-Weinberg Principle?
Large Random MandM ## Footnote This helps recall the five assumptions: Large Population, Random Mating, No Migration, No Mutation, No Selection.
117
What is the first step in approaching **Hardy-Weinberg questions**?
Identify the frequency of the homozygous recessive population ## Footnote This frequency is often provided directly in the question.
118
In Hardy-Weinberg, what does **q** represent?
Homozygous recessive individuals ## Footnote You can deduce the frequency of the recessive allele (q) by taking the square root of the homozygous recessive population.
119
How do you find the frequency of the **dominant allele (p)** in Hardy-Weinberg?
Use the equation p + q = 1 ## Footnote This allows you to solve for p once you have q.
120
What is the formula for the **heterozygous population** in Hardy-Weinberg?
2pq ## Footnote This represents the frequency of heterozygous individuals in the population.
121
What does **p** represent in Hardy-Weinberg?
Homozygous dominant population ## Footnote This is one of the key values used in the Hardy-Weinberg equations.
122
What is the equation for the frequency of the **dominant phenotype**?
p + 2pq ## Footnote This equation combines the frequencies of homozygous dominant and heterozygous individuals.
123
What does **q'** represent in Hardy-Weinberg?
Homozygous recessive population ## Footnote This is another notation for the frequency of homozygous recessive individuals.
124
What is the frequency of the **recessive phenotype** denoted as?
q ## Footnote This represents the frequency of individuals expressing the recessive trait.
125
What do **genetic inheritance patterns** dictate?
The transmission of traits from parents to offspring ## Footnote Understanding these patterns is crucial for genetic analysis.
126
What is **Autosomal Dominant** inheritance?
* Inheritance of a dominant gene on an autosomal chromosome * Affected individuals have a 50% chance of passing the gene ## Footnote Examples include Huntington's disease and Marfan syndrome.
127
What is required for **Autosomal Recessive** inheritance to express a trait?
Two copies of a recessive gene ## Footnote Typically skips generations; carriers are asymptomatic. Examples include cystic fibrosis and sickle cell anemia.
128
What characterizes **X-linked Dominant** inheritance?
* Dominant gene on the X chromosome * Affects both males and females, with varying expressivity ## Footnote An example is Rett Syndrome.
129
What is the main feature of **X-linked Recessive** inheritance?
* Recessive gene on the X chromosome * More common in males; females are often carriers ## Footnote Examples include hemophilia and color blindness.
130
How is **Mitochondrial** inheritance characterized?
* Inherited from the mother through mitochondrial DNA * Affects both males and females, but only females pass it on ## Footnote Examples include mitochondrial myopathy and Leber's hereditary optic neuropathy.
131
What is a **Punnett Square** used for?
Predicting the genetic outcomes of a cross between two individuals ## Footnote It illustrates and predicts the inheritance of traits in offspring.
132
What does a **Monohybrid Cross** analyze?
A single gene ## Footnote It focuses on the inheritance of one trait.
133
What does a **Dihybrid Cross** examine?
Two genes simultaneously ## Footnote It assesses the inheritance of two traits at once.
134
What is the purpose of a **Test Cross**?
To determine whether a dominant phenotype's genotype is homozygous dominant or heterozygous ## Footnote It involves crossing with a known homozygous recessive.
135
If a dominant phenotype is **heterozygous**, what percentage of the offspring will express the recessive phenotype?
50% ## Footnote This occurs when crossed with a homozygous recessive.
136
If a dominant phenotype is **homozygous dominant**, what will be the outcome for the recessive phenotype in offspring?
0 offspring will express recessive phenotype ## Footnote This indicates that all offspring will express the dominant trait.
137
What does **P** refer to in Mendelian genetic terminology?
Parental generation ## Footnote P refers to the original set of parents crossed.
138
What does **F1** represent in Mendelian genetics?
Filial 1 generation ## Footnote F1 refers to the first generation of progeny from the P generation.
139
What does **F2** signify in Mendelian genetics?
Filial 2 generation ## Footnote F2 refers to the first generation of progeny from the F1 generation.
140
In a pedigree chart, what does a **line of descent** indicate?
The lineage or ancestry of individuals ## Footnote It shows how traits are passed through generations.
141
What does the **marriage line** represent in a pedigree chart?
The union between two individuals ## Footnote It connects partners in a marriage or mating.
142
In a pedigree chart, how is a **deceased** individual typically represented?
By a line crossing through their symbol ## Footnote This indicates that the individual is no longer living.
143
True or false: The **sibling line** in a pedigree chart connects siblings.
TRUE ## Footnote It visually represents the relationship between brothers and sisters.
144
What does the term **twins** refer to in Mendelian genetics?
Individuals born at the same time from the same pregnancy ## Footnote Twins can be identical or fraternal.
145
What does **II** indicate in a pedigree chart?
Generation number ## Footnote It shows the specific generation of individuals in the lineage.
146
What does **gene mapping** refer to?
Maps physical location of genes on the chromosome ## Footnote It helps in understanding the arrangement and distance between genes.
147
In gene mapping, what happens as the **distance between genes** increases?
Increased crossover frequency ## Footnote This leads to increased recombination.
148
What occurs during **genetic recombination**?
Occurs between maternal and paternal sister chromatids ## Footnote This process is essential for genetic diversity.
149
What is a **centimorgan** or **map unit**?
Unit of measurement of distance on chromosome ## Footnote It quantifies genetic linkage.
150
What does a distance of **one centimorgan** indicate?
Distance between genes for which one product of meiosis in 100 is recombinant ## Footnote This reflects the likelihood of recombination occurring.
151
If there are **25 map units** between two genes, what percentage of the time will recombination occur?
25% of the time ## Footnote This indicates the frequency of recombination with respect to the two genes within the map unit distance.
152
What does **evolutionary fitness** denote?
An organism's ability to survive, reproduce, and pass on its genetic material ## Footnote Example: A strong and healthy individual but cannot reproduce has fitness of zero.
153
What is **natural selection**?
A fundamental mechanism of evolution where heritable traits contributing to survival and reproduction become more prevalent ## Footnote It operates over generations.
154
Define **group selection**.
Posits that traits promoting the success of a group can undergo natural selection ## Footnote It differs from individual selection by focusing on group success.
155
What is **collective fitness**?
Considers the collective fitness and success of a population ## Footnote Unlike traditional natural selection, it emphasizes group dynamics.
156
What does **selection by differential reproduction** emphasize?
Variations in reproductive success among individuals based on their traits ## Footnote Individuals with advantageous traits contribute more offspring.
157
What is **altruism** in the context of evolutionary success?
Behaviors benefiting others at a cost to oneself ## Footnote It seems to contradict individual fitness.
158
Define **inclusive fitness**.
Reconciles altruistic behaviors by considering the reproductive success of close relatives ## Footnote It highlights the genetic connections in altruism.
159
What is **kin selection**?
Altruistic traits favored by natural selection if they enhance reproductive success of genetically related individuals ## Footnote It contributes to evolutionary success through shared genes.
160
What is **speciation**?
Formation of new and distinct species in evolution ## Footnote Needed conditions: ability to interbreed and produce fertile, viable offspring.
161
Define **polymorphism**.
Coexistence of multiple genetic variants or alleles within a population ## Footnote Example: A yellow jaguar and a black jaguar.
162
What is **specialization** in evolutionary terms?
Evolutionary specialization occurs when a species develops unique traits to adapt to a specific ecological niche ## Footnote Example: The anteater's long tongue and specialized claws are adaptations for feeding on ants.
163
What happens during **competition** in ecology?
Occurs when ecological niches overlap, competing on resources to survive in its environment ## Footnote Controls population growth, decreased resources lead to increased competition and decreased population growth.
164
What is **selective breeding**?
Controlled mating to enhance desirable traits ## Footnote This method is used to improve specific characteristics in plants or animals.
165
Define **inbreeding**.
Mating closely related individuals to maintain specific traits but risking genetic disorders ## Footnote This practice can lead to a higher chance of genetic issues.
166
What is **outbreeding**?
Mating less closely related individuals to introduce genetic diversity ## Footnote This can help reduce the risk of genetic disorders.
167
What does **hybridization** involve?
Crossing genetically different individuals to combine favorable traits ## Footnote This can lead to offspring with enhanced characteristics.
168
Define **crossbreeding**.
Mating individuals from different breeds to improve overall characteristics ## Footnote This is often used in agriculture to enhance crop or livestock traits.
169
What is **artificial selection**?
Human-driven process influencing traits in successive generations for desired outcomes in plants or animals ## Footnote This method is commonly used in agriculture and animal husbandry.
170
What is **genetic drift**?
Random changes in a population (i.e., random changes in allele frequencies) ## Footnote Increased bottlenecks lead to decreased population size and increased chance of genetic drift.
171
What is **adaptation** in the context of evolution?
Genetic change in a population caused by natural selection ## Footnote Example: The elongated beak of hummingbirds enables access to nectar in tubular flowers, enhancing survival and reproduction.
172
What is a **bottleneck** in population genetics?
Severe reduction in population size ## Footnote Reduces genetic diversity and can be caused by natural disasters.
173
Define **parallel evolution**.
Two or more related species evolve independently but show similar adaptations due to comparable environmental pressures ## Footnote Example: Marsupial mammals in Australia and placental mammals in other continents exhibit similar ecological roles.
174
What is the outcome of **divergent evolution**?
Species with a common ancestor develop different traits and adapt to different environmental niches ## Footnote Example: Darwin's finches in the Galápagos Islands evolved different beak shapes in response to varied food sources.
175
What characterizes **convergent evolution**?
Unrelated species develop similar traits due to adaptation to similar environments ## Footnote Example: The wings of bats and birds evolved independently but both allow for flight.
176
What is measured to determine **Evolutionary Time**?
Amount of time passed by measuring amount of neutral mutations ## Footnote Neutral mutations are random mutations not acted on by natural selection.
177
Define **neutral mutations**.
Random mutations (drift) not acted on by natural selection ## Footnote These mutations are used to compare genome differences between species.
178
How can scientists find out how long ago two species **diverged**?
By comparing genome differences between the two species ## Footnote This method relies on measuring neutral mutations.
179
Why is preserving **biodiversity** crucial for medicine?
* Medical advancements * Human health * Sustainability of healthcare resources ## Footnote Biodiversity is essential for diverse healthcare options.
180
List the three types of **Diversity Essentials** that impact human health.
* Genetic diversity * Species diversity * Ecosystem diversity ## Footnote These diversities are critical for medical discoveries.
181
How does **biodiversity** support health?
* Clean air * Clean water * Medicinal resources ## Footnote Ecosystem resilience is enhanced by biodiversity.
182
What are some **health threats** posed by environmental changes?
* Habitat loss * Pollution * Climate change ## Footnote These factors can affect disease patterns.
183
What is the role of **conservation** in medicine?
Safeguards potential medicinal resources ## Footnote Ensures diverse healthcare options through preservation.
BIOMOLECULES
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