science

Heredity

  • Unit Description: This unit explores the mechanisms of inheritance and how traits are passed down.

Key Concepts:

  • Meiosis and Mitosis:

    • Mitosis: Responsible for growth and repair; produces two genetically identical daughter cells.

    • Meiosis: Involved in sexual reproduction; produces four daughter cells with half the chromosomes, ensuring genetic diversity.

  • Mendel's Laws of Inheritance: Foundation for understanding genetics by Gregor Mendel.

    • First Law (Law of Segregation): Alleles for a trait separate during gamete formation; each gamete receives one allele.

    • Second Law (Law of Independent Assortment): Different trait alleles segregate independently during gamete formation.

    • Third Law (Law of Dominance): Dominant alleles mask recessive alleles' expression.

  • Non-Mendelian Genetics:

    • Incomplete Dominance: Neither allele is fully dominant; results in a blended phenotype.

    • Codominance: Both alleles are expressed equally.

    • Sex-linked Inheritance: Traits carried on sex chromosomes (X or Y).

  • Family Pedigree: Diagram to track trait inheritance and genetic disorders.

Evolution

  • Unit Description: This unit explores evolution theory, evidence, and mechanisms.

Key Concepts:

  • Scientists Contributing to Evolution:

    • Charles Darwin: Proposed natural selection as a key evolutionary process.

    • Alfred Russel Wallace: Independently proposed a similar theory of natural selection.

    • Jean-Baptiste Lamarck: Proposed inheritance of acquired characteristics (disproved).

  • Evidence for Evolution:

    • Fossil Record: Shows organism changes over time.

    • Comparative Anatomy: Similarities indicate common ancestry.

    • Comparative Embryology: Early developmental similarities among species.

    • Biogeography: Geographic species distribution supports evolution.

    • Molecular Biology: DNA/protein similarities among species support common ancestry.

  • Mechanisms of Evolution:

    • Natural Selection: Organisms with adaptive traits survive and reproduce more.

    • Genetic Drift: Random changes in allele frequencies, significant in small populations.

    • Gene Flow: Allele movement between populations.

    • Mutation: DNA sequence changes introduce new alleles.

  • Patterns of Evolution:

    • Convergent Evolution: Unrelated species evolve similar traits under similar pressures.

    • Divergent Evolution: Related species evolve different traits due to varied pressures.

  • Survival of the Fittest: Adapted individuals are more likely to survive and reproduce.

  • Speciation: Formation of new species.

    • Allopatric Speciation: Geographical isolation.

    • Sympatric Speciation: Occurs in the same area, often through reproductive isolation.

  • Punctuated Equilibrium: Long periods of stability interrupted by rapid evolutionary changes.

  • Hardy-Weinberg Equilibrium: Conditions for stable allele and genotype frequencies.

Prokaryotes, Protista, and Fungi

  • Unit Description: Characteristics, diversity, and importance of these groups.

Key Concepts:

  • Cell Structure:

    • Prokaryotic Cells: No nucleus or membrane-bound organelles; single circular chromosome.

    • Eukaryotic Cells: Have nucleus and organelles; multiple linear chromosomes.

  • Types of Cells:

    • Prokaryotic: Bacteria, archaea.

    • Eukaryotic: Protists, fungi, plants, animals.

  • Viruses: Non-living, require host for replication.

  • Kingdom Bacteria and Archaea:

    • Characteristics: Unicellular, prokaryotic, metabolically diverse.

    • Examples: E. coli, Salmonella.

    • Classification: Based on shape, gram staining, metabolic processes.

  • Kingdom Protista:

    • Characteristics: Eukaryotic, mostly unicellular.

    • Examples: Amoeba, algae.

    • Classification: By nutrition and reproduction modes.

  • Kingdom Fungi:

    • Characteristics: Eukaryotic, heterotrophic, can be saprophytic or parasitic.

    • Examples: Mushrooms, yeasts.

    • Roles: Decomposers, symbionts.

Animalia

  • Unit Description: Characteristics and major organ systems in animals.

Key Concepts:

  • Kingdom Animalia:

    • Characteristics: Eukaryotic, multicellular, heterotrophic, motile.

    • Examples: Sponges, fish, mammals.

    • Classification: Based on body plan, symmetry, tissue organization, and development.

  • Phyla Characteristics:

    • Porifera (Sponges): Simple multicellular, filter feeders.

    • Cnidaria (Corals): Radial symmetry, stinging cells.

    • Annelida (Segmented Worms): True body cavity and segmentation.

    • Chordata (Vertebrates): Notochord and dorsal nerve cord.

  • Organ Systems:

    • Respiratory: Varies across groups; humans have complex structures for gas exchange.

    • Circulatory: Closed system in Chordata; open system in Arthropoda.

    • Digestive: Complete digestive tracts in most kingdoms; varied structures across groups.

Plant Unit

  • Unit Description: Diversity, classification, and adaptations of plants.

Key Concepts:

  • Plant Classification:

    • Bryophytes: Non-vascular plants like mosses.

    • Tracheophytes: Vascular plants; includes ferns (spore producers) and seed plants (spermatophytes).

  • Alternation of Generations: Life cycle alternates between haploid and diploid generations.

  • Adaptations to Land:

    • Roots: Absorb water and nutrients.

    • Stems: Structural support.

    • Leaves: Site of photosynthesis, equipped with cuticles and stomata.

  • Dicots vs Monocots:

    • Dicots: Two cotyledons, net-like veins.

    • Monocots: One cotyledon, parallel leaf veins.

Structure, Function, and Classification

  • Description: Principles of classification and organism function.

Key Concepts:

  • Linnaean System: Hierarchical biological classification.

  • Binomial Nomenclature: Two-name system for species identification.

  • Relationships: Structure-function relationships are key in classification.

  • Coevolution: Evolutionary adaptations in response to one another.

Practice Questions

  • Description: Series of assessment questions to evaluate understanding of the units covered.

    • Types: Multiple choice, short answer, and essay questions for concept synthesis.

Systems Review

  • Description: Review of organ systems in animals, highlighting key structures and functions.

Key Concepts:

  • Phyla Summary Table: Key characteristics including anatomy, reproduction, and digestive/respiratory/circulatory systems.

  • Dichotomous Keys and Phylogenetic Trees: Tools for classification and understanding evolutionary relationships.

Diagrams

  • Respiratory System: Diagram labeling structure of the human respiratory system.

  • Phylogenetic Tree: Diagram showing evolutionary relationships among organisms.

The Human Respiratory System:

  • Pharynx: Pathway for air; connects the nasal cavity and mouth to the larynx.

  • Epiglottis: Flap that prevents food from entering the trachea.

  • Larynx: Voice box; contains vocal cords and is important for phonation.

  • Trachea: Windpipe; a tube that connects the larynx to the bronchi.

  • Bronchi: Two main branches from the trachea leading to the lungs.

  • Bronchioles: Smaller branches of the bronchi that lead to alveoli.

  • Diaphragm: Muscle that aids in respiration; contracts during inhalation and relaxes during exhalation.

  • Inhalation: The process of taking air into the lungs.

  • Exhalation: The process of expelling air from the lungs.

  • Control of Respiration: Role of blood concentration of CO2; brain (medulla oblongata) regulates breathing; diaphragm and lungs work together to facilitate breathing.

The Human Circulatory System:

  • Heart: Muscular organ that pumps blood throughout the body.

  • Ventricles: Lower chambers of the heart responsible for pumping blood.

  • Atria: Upper chambers of the heart that receive blood.

  • Vessels: Tubes that carry blood throughout the body; include arteries, veins, and capillaries.

  • Arteries: Carry oxygenated blood away from the heart (except pulmonary arteries).

  • Veins: Carry deoxygenated blood back to the heart (except pulmonary veins).

  • Capillaries: Microscopic vessels where gas and nutrient exchange occurs.

  • Oxygenated blood: Blood rich in oxygen.

  • Deoxygenated blood: Blood low in oxygen and high in carbon dioxide.

  • Aorta: Main artery that carries blood from the heart to the rest of the body.

  • Vena cava: Large veins that carry deoxygenated blood back to the heart.

The Human Digestive System:

  • Mouth: Begins digestion with chewing and saliva.

  • Teeth: Mechanically break down food into smaller pieces.

  • Amylase: Enzyme in saliva that starts breaking down carbohydrates.

  • Esophagus: Tube that connects the mouth to the stomach; uses peristalsis to move food.

  • Peristalsis: Wave-like muscle contractions that move food through the digestive tract.

  • Stomach: Acidic environment for food breakdown; contains gastric acid and pepsin for protein digestion.

  • Small Intestine: Main site for nutrient absorption; lined with villi and microvilli.

  • Large Intestine: Absorbs water and forms feces.

  • Villi: Small finger-like projections that increase surface area for absorption.

  • Microvilli: Even smaller projections on villi that further increase absorption area.

  • Microorganisms: Beneficial bacteria that aid digestion in the gut.

  • Rectum: Final section of the large intestine, stores feces.

  • Anus: Opening through which feces are expelled.

  • Liver: Produces bile; essential for fat digestion.

  • Gallbladder: Stores bile until it's needed for digestion.

  • Dissection: The process of cutting into organisms to study their internal structures.