Biodiversity and Genetic Diversity Quiz

Biodiversity

• Species Diversity: Variety and abundance of species in a region.
• Genetic Diversity: Variety of heritable traits within a breeding population. This is known as the gene pool, the sum of all gene versions in a population. Variations in genetic makeup lead to differences among individuals.
• Ecosystem Diversity: Variety of ecosystems within the biosphere, incorporating both biotic (living) and abiotic (non-living) factors. The physical and chemical variations across the Earth's surface contribute to this diversity.

Genetic Diversity and Resistance

• Disease Resistance: If no individuals in a population have traits resistant to a disease, the entire population could be wiped out. Genetic diversity allows populations to endure changing conditions like shifts in prey/predator numbers, climate changes, etc.
• Conservation Biology: Understanding genetic diversity helps scientists support struggling populations.

Ecosystem Diversity and Services

• Ecosystem Services: Benefits humans and other organisms receive from healthy, sustainable ecosystems. Ecosystem diversity is linked to the many services ecosystems provide, such as habitat provision, recreation, and ecological controls like pest regulation. Without this diversity, Earth would lose many essential services.

Prokaryotic Cells (Bacteria and Archaea)

• Characteristics: Tiny, single-celled organisms lacking membrane-bound organelles. Their DNA is in a circular form (plasmid).
• Structure: Cell wall for protection and support, peptidoglycan (Bacteria) or unique components (Archaea), cell membrane for substance control, and nucleoid region housing DNA. May possess flagella (movement) or pili (various functions).
• Capsule: Allows attachment to surfaces and defense against immune systems. Consists of water to prevent dehydration
• Cell Wall: Provides rigidity, support, and protection. Made of peptidoglycan in bacteria.
• Cell Membrane: Controls movement of substances in and out of the cell.
• Nucleoid: Contains the cell's DNA and RNA.
• Pili: Hair-like structures assisting in movement, genetic exchange, and attachment.

Archaea vs. Bacteria

• Key Differences: Archaea's cell membranes and cell wall components differ significantly from bacteria. Archaea resemble eukaryotes more genetically.
• Archaea Traits: Can thrive in extreme environments (e.g., high temperatures, high salinity). Some are methanogens (produce methane in oxygen-free environments), mutualistic, and play roles in decomposition and digestion.
• Bacteria Traits: Varied characteristics depending on cell wall structure, movement types (flagella, cilia, non-motile), and metabolic strategies.

Bacterial Classification

• Gram Stain: Classifies bacteria based on their reaction to a dye (crystal violet and iodine). Gram-positive bacteria absorb the stain; gram-negative do not. Gram-negative bacteria are often more pathogenic (causing disease).

Bacterial Reproduction

• Binary Fission: Asexual reproduction resulting in two identical daughter cells. Extremely rapid reproduction (e.g., every 20 minutes).
• Conjugation: Transfer of genetic material (often plasmids) between bacteria through a hollow pilus. This method contributes to genetic variation.
• Antibiotic Resistance: Mutations in bacteria can impart resistance to antibiotics due to alterations in cell wall formation, cellular processes, or reproduction. Resistance can spread rapidly due to conjugation and binary fission.
• Endospore Formation: Protective structure forming around the DNA during environmental stress (nutrient deficiency, high temperatures, radiation). Ensures the survival of the bacterial DNA. Endospores of certain species like tetanus and anthrax can persist in soil for long periods.

Viruses

• Definition: Non-living, non-cellular particles much smaller than cells and lacking the equipment to survive and replicate independently; require host cells.
• Characteristics: Infect cells and hijack their machinery to replicate, but they don't utilize ATP, create waste, or grow.
• Size: Very small, typically hundreds of thousands can fit into a human cell.

Test your knowledge on biodiversity, including species, genetic, and ecosystem diversity. Explore the importance of genetic variation in disease resistance and conservation biology. This quiz dives into the fundamental concepts of biodiversity and its critical role in ecosystems.