Genetics: Phenotypes and Alleles

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Questions and Answers

What is the term used to describe the physical expression of a gene?

Allele

Phenotype (correct)

Gene pool

Genotype

Which of the following mechanisms can change allele frequencies in populations?

Sexual reproduction

Environmental competition

Sustainability practices

Natural selection (correct)

At what levels can genetic diversity be measured?

Individual, species, and community

Population, species, community, and biome (correct)

Organism, population, and family

Genotype, phenotype, and allele

What is the term for the combination of all genes, including alleles, present in a reproducing population?

Gene pool Signup and view all the answers

How does genetic diversity primarily arise within a population?

Mutation Signup and view all the answers

What primarily determines the number of species on an island according to the Equilibrium Theory of Island Biogeography?

Extinction and immigration rates Signup and view all the answers

Which of the following factors does NOT influence the equilibrium number of species on an island?

Presence of predators Signup and view all the answers

Which of the following scenarios could act as a climatic barrier to species distribution?

High levels of moisture and sunlight Signup and view all the answers

Which event can lead to variations in species distribution related to geographic constraints?

Continental drift Signup and view all the answers

What is the primary mechanism implied by the equilibrium theory regarding species composition?

Constant turnover in species Signup and view all the answers

What is the primary benefit of establishing wildlife corridors?

They connect critical habitats Signup and view all the answers

Which type of species is most likely to be affected by habitat fragmentation due to their large area needs?

Area sensitive species Signup and view all the answers

How do edge habitats affect wildlife populations negatively?

By attracting more invasive species Signup and view all the answers

What best describes the allopatric speciation process?

Populations become geographically isolated Signup and view all the answers

Which phenomenon is characterized by a decrease in dispersal due to fragmentation?

Faunal relaxation Signup and view all the answers

Which of the following is a characteristic of sympathetic speciation?

New species emerge within the same area Signup and view all the answers

What is an insularization effect in the context of habitat fragmentation?

Isolation of populations Signup and view all the answers

Which type of species is most likely to be listed as rare due to habitat loss?

Specialists or highly coevolved species Signup and view all the answers

Which factor is NOT a fundamental concept in biogeography?

Climatology Signup and view all the answers

What is one characteristic of the Paleactic realm?

Includes temperate Eurasia and northern Africa Signup and view all the answers

Which biogeographic realm is home to great apes like the Gorilla?

Ethiopian Signup and view all the answers

Which of the following is a primary reason for species variation in biogeography?

Geographical isolation Signup and view all the answers

What role do physical barriers play in biogeography?

Limit the distribution of organisms Signup and view all the answers

Which of the following organisms is typically found in the Oriental realm?

Lower apes such as macaques Signup and view all the answers

Which biome's distribution is most closely associated with climate?

All terrestrial biomes Signup and view all the answers

What is meant by 'endemic areas' in biogeography?

Places where species are native and restricted to that locality Signup and view all the answers

Which statement about the Nearctic realm is true?

It covers temperate North America Signup and view all the answers

Dispersal in biogeography refers to what process?

The movement of populations away from their original location Signup and view all the answers

Which group of animals in the Philippines has the highest number of endemic species?

Amphibians Signup and view all the answers

What percentage of reptile species in the Philippines are considered endemic?

82% Signup and view all the answers

How many species of mammals are found in the Philippines, according to the given data?

179 Signup and view all the answers

Which category has the largest estimated number of species present in the Philippines?

Insects Signup and view all the answers

Among birds in the Philippines, how many species are known to be migratory?

Around 100 Signup and view all the answers

What is the number of venomous snake species that are endemic to the Philippines?

7 Signup and view all the answers

How many threatened mammal species are recorded in the Philippines?

52 Signup and view all the answers

How many species of corals are endemic to the Philippines?

12 Signup and view all the answers

What is the total number of reptiles documented in the Philippines?

270 species Signup and view all the answers

Which animal category has the least number of documented species in the Philippines?

Corals Signup and view all the answers

Study Notes

Genetic Diversity and Phenotypes

Phenotype refers to the physical expression of genes and determines observable traits.
Genetic information involves the alleles, or variants of a gene, affecting traits such as eye color.
Diversity can be measured at population, species, community, and biome levels.
Genetic diversity contributes to survival and reproduction across these levels.
Mechanisms changing allele frequencies include selection, mutation, migration, and genetic drift, leading to evolution.
The gene pool encompasses all genes and alleles in a reproducing population.

Megadiversity Countries

17 nations host over two-thirds of Earth’s biological resources, representing significant cultural diversity.
These megadiversity countries harbor 80% of the world's most endangered species.

Philippine Faunal Diversity

Amphibians: 111 species, with 82 unique to the Philippines.
Reptiles: 20 snake species, 270 total; 82% are endemic.
Birds: 576 species, 192 endemic; high migratory variation.
Mammals: 179 species, 52 threatened; 111 unique to the Philippines.
Insects: Over 20,940 species, roughly 69.8% endemic.
Corals: 12 endemic species; recent discoveries include a new Leptoseris species.

Biogeography Fundamentals

Biogeography synthesizes multiple disciplines, including ecology, evolution, and geology.
Key concepts include evolution, extinction, dispersal, and species variation.
Biogeographers recognize six distinct realms based on species distribution and relationships:
- Paleactic: Europe and Asia with unique salamander species.
- Oriental: Lower apes in tropical Asia.
- Ethiopian: Great apes in Sub-Saharan Africa.
- Australian: Marsupials in Australia and surrounding areas.
- Nearctic: Unique taxa in North America.
- Neotropic: Rich diversity in Central and South America.

Island Biogeography Theory

Species diversity on islands is dependent on equilibrium rates of extinction and immigration.
The equilibrium number of species is influenced by island size and distance from the mainland.
Wildlife corridors are crucial for maintaining species connectivity and reducing isolation effects.

Fragmentation Effects

Fragmentation reduces total habitat area, leading to biodiversity loss and small population effects.
It can create isolated habitats, decreasing dispersal and increasing vulnerability.
Edge habitats often contribute to predation risks, invasive species infestations, and microclimate alterations.

Species Vulnerability to Fragmentation

Area sensitive: Require large territories (e.g., large carnivores).
Isolation sensitive: Depend on specific dispersal habitats.
Edge sensitive: Struggle in fragmented environments.
Rare species: More prone to extinction due to reduced habitat and population sizes.
Specialists: Need specific conditions and habitats for survival.

Environmental Factors Influencing Biodiversity

Climate, historical factors, and geographical constraints (such as continental drift and glaciation) shape species distribution.
Barriers to distribution include physical, climatic, and biotic factors affecting organism survival and migration.

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Description

Explore the physical expression of genes through this quiz on phenotypes and genetic diversity. Test your knowledge on how alleles, entire genes, and chromosomal structures contribute to various traits such as eye color. Understand the measurement of genetic variability and its implications.