level c English : diversity unit flash card

Diversity Unit Test Notes

  • What is Biology?

  • Biology is the study of living things, how they grow, change, and interact with their environment.

  • 7 Characteristics of Living Things

  • 1. Made of cells – All living things have one or more cells.

  • 2. Grow and develop – They get bigger and change over time.

  • 3. Reproduce – They make more of their own kind.

  • 4. Use energy – They need food or sunlight to stay alive.

  • 5. Respond to environment – They react to things like light, heat, and danger.

  • 6. Maintain balance (homeostasis) – They keep their body conditions stable.

  • 7. Evolve – Over many years, species change to survive better.

  • Diversity, Species, Hybrid, Morphology, Biological Classification

  • • Diversity – The variety of living things.

  • • Species – A group of organisms that can reproduce and have fertile offspring.

  • • Hybrid – An organism from two different species (e.g., mule = horse + donkey).

  • • Morphology – The shape and structure of organisms.

  • • Biological classification – Grouping organisms based on similarities.

  • Forms of Diversity Among Species

  • • Food supply – Different species eat different things.

  • • Protection – Some have shells, others have sharp teeth.

  • • Transportation – Some fly, others swim or walk.

  • • Reproduction – Some lay eggs, others give birth.

  • • Hygiene – Some clean themselves, others rely on bacteria.

  • • Digestion – Some have one stomach, others multiple stomachs.

  • Ways Diversity is Lost

  • • Habitat destruction (cutting forests, building cities).

  • • Pollution (chemicals in water, air, and land).

  • • Overhunting or overfishing.

  • • Climate change (temperature changes harm species).

  • Dichotomous Keys

  • A tool used to identify organisms based on questions with two choices (e.g., “Does it have wings? Yes/No”).

  • Ecological Important Classification

  • Organisms are grouped by their role in the environment (producers, consumers, decomposers).

  • Taxonomy & Its Importance

  • Taxonomy is the science of classifying living things. It helps scientists organize and study organisms.

  • Father of Taxonomy

  • Carl Linnaeus – Created a system to name and classify organisms.

  • Binomial Nomenclature

  • A two-part scientific naming system using Latin (e.g., Homo sapiens for humans). It helps scientists worldwide understand species.

  • Linnaean Classification System (Kingdom to Species)

  • A way to classify organisms from broad to specific:

  • Kingdom → Phylum → Class → Order → Family → Genus → Species

  • Mnemonic: King Phillip Comes Over For Good Spaghetti

  • Phylogeny

  • The study of evolutionary history and relationships between organisms.

  • Clade

  • A group of organisms that share a common ancestor.

  • Three Domains & Their Kingdoms

  • 1. Bacteria – Kingdom: Bacteria

  • 2. Archaea – Kingdom: Archaea

  • 3. Eukarya – Kingdoms: Protista, Fungi, Plantae, Animalia

  • Prokaryotes vs. Eukaryotes

  • • Prokaryotes – No nucleus (e.g., bacteria).

  • • Eukaryotes – Have a nucleus (e.g., plants, animals).

  • Pathogen

  • A microorganism that causes disease (e.g., bacteria, viruses, fungi).

  • Importance of Prokaryotes

  • • Decomposers (break down dead organisms).

  • • Help in digestion.

  • • Used in making yogurt and medicine.

  • Mutualism & Examples

  • A relationship where two organisms help each other.

  • Example: Bees and flowers – Bees get nectar, flowers get pollinated.

  • Bacteriophages

  • Viruses that infect bacteria.

  • Six Major Groups of Bacteria

  • 1. Proteobacteria – Found in soil and water.

  • 2. Cyanobacteria – Photosynthetic bacteria.

  • 3. Gram-positive bacteria – Some cause diseases.

  • 4. Spirochetes – Spiral-shaped bacteria.

  • 5. Chlamydiae – Parasitic bacteria.

  • 6. Bacteroidetes – Found in human intestines.

  • Bacterial Characteristics

  • • Shape – Round (coccus), Rod (bacillus), Spiral (spirillum).

  • • Structure – Cell wall, DNA, flagella for movement.

  • • Metabolism – Some need oxygen (aerobic), others don’t (anaerobic).

  • • Reproduction – Binary fission (splitting into two).

  • Examples of Bacterial Diseases

  • • Tuberculosis

  • • Strep throat

  • • Lyme disease

  • Antibiotics

  • Medicines that kill bacteria, but don’t work on viruses.

  • How Bacteria Become Resistant to Antibiotics

  • Bacteria evolve and develop ways to survive antibiotics, making infections harder to treat.

  • Archaea Groups & Features

  • • Methanogens – Live in no oxygen areas, produce methane gas.

  • • Halophiles – Live in very salty water.

  • • Thermophiles – Live in extreme heat.

  • • Psychrophiles – Live in extreme cold.

  • Methanogenesis

  • A process where methanogens make methane gas.

  • Habitats of Extremophiles

  • Found in volcanoes, deep-sea vents, salt lakes, and icy places.

  • Viruses & Structure

  • Viruses are tiny particles that infect cells.

  • • Made of DNA or RNA inside a protein coat.

  • • Cannot reproduce on their own (need a host cell).

  • Importance of Viruses

  • • Some cause diseases (flu, COVID-19).

  • • Some are used in gene therapy.

  • Examples of Disease-Causing Viruses

  • • Influenza (flu)

  • • HIV/AIDS

  • • COVID-19

  • Epidemic vs. Pandemic

  • • Epidemic – A disease that spreads in one area.

  • • Pandemic – A disease that spreads worldwide.

  • Classification & Phylogeny of Viruses

  • Viruses are grouped by shape, type of genetic material (DNA or RNA), and how they infect cells.

  • Lytic vs. Lysogenic Cycle

  • • Lytic cycle – Virus enters a cell, makes copies, and bursts the cell.

  • • Lysogenic cycle – Virus hides in the DNA and later becomes active.

  • Lysis, Lysogeny, Transduction, Gene Transfer

  • • Lysis – Cell bursts, releasing new viruses.

  • • Lysogeny – Virus DNA stays inside host DNA.

  • • Transduction – Virus transfers genes between bacteria.

  • • Gene transfer – Movement of genes between organisms.

  • Viral Diseases & Transmission

  • • Airborne – Flu, COVID-19 (spread by sneezing, coughing).

  • • Direct contact – HIV (spread by blood, bodily fluids).

  • • Insect bites – West Nile virus (spread by mosquitoes).

  • Gene Therapy, Viroids, Prions

  • • Gene therapy – Using viruses to fix genetic diseases.

  • • Viroids – Small pieces of RNA that infect plants.

•Prions – Misfolded proteins that cause brain diseases (e.g., Mad Cow Disease)