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Lesson 2NAT Grade 10

Science

Biology, Chemistry, Physics, and Earth Science - Integrated Topics

Table of Contents

1. Biology: Cell Theory and Genetics

Cell Theory

  1. 1. All living things are made of cells
  2. 2. Cells are the basic unit of life
  3. 3. All cells come from pre-existing cells

Cell Types

Prokaryotic

  • β€’ No nucleus (DNA free in cytoplasm)
  • β€’ No membrane-bound organelles
  • β€’ Smaller (1-10 ΞΌm)
  • β€’ Example: Bacteria

Eukaryotic

  • β€’ Has nucleus (DNA enclosed)
  • β€’ Has membrane-bound organelles
  • β€’ Larger (10-100 ΞΌm)
  • β€’ Example: Plants, Animals, Fungi

Cell Organelles

OrganelleFunction
NucleusControl center, contains DNA
MitochondriaPowerhouse - produces ATP (energy)
RibosomeProtein synthesis
Endoplasmic ReticulumTransport system (Rough=proteins, Smooth=lipids)
Golgi ApparatusPackaging and secretion
Chloroplast (plants)Photosynthesis
Cell Wall (plants)Support and protection

Genetics: DNA and Inheritance

DNA Structure

  • β€’ Double helix structure (Watson & Crick)
  • β€’ Made of nucleotides: Sugar + Phosphate + Base
  • β€’ Base pairs: A-T (Adenine-Thymine), G-C (Guanine-Cytosine)

Punnett Square

Used to predict offspring genotypes and phenotypes

  • β€’ Dominant (capital letter) - expressed even if only one copy
  • β€’ Recessive (lowercase) - expressed only if two copies
  • β€’ Homozygous: AA or aa | Heterozygous: Aa

2. Chemistry: Periodic Table and Bonding

Atomic Structure

  • β€’ Protons - positive charge, in nucleus (defines element)
  • β€’ Neutrons - no charge, in nucleus
  • β€’ Electrons - negative charge, orbit nucleus

Periodic Table Groups

GroupNamePropertiesExamples
1Alkali MetalsSoft, reactive, 1 valence electronLi, Na, K
2Alkaline Earth Metals2 valence electronsMg, Ca
17Halogens7 valence electrons, reactiveF, Cl, Br, I
18Noble Gases8 valence electrons, stableHe, Ne, Ar

Chemical Bonding

Ionic Bond

Transfer of electrons

Metal + Nonmetal (NaCl)

Covalent Bond

Sharing of electrons

Nonmetal + Nonmetal (Hβ‚‚O)

Metallic Bond

Sea of electrons

Metal + Metal (Cu, Fe)

Chemical Reactions

Types of Reactions:

  • β€’ Synthesis: A + B β†’ AB
  • β€’ Decomposition: AB β†’ A + B
  • β€’ Single Replacement: A + BC β†’ AC + B
  • β€’ Double Replacement: AB + CD β†’ AD + CB
  • β€’ Combustion: Fuel + Oβ‚‚ β†’ COβ‚‚ + Hβ‚‚O + Energy

3. Physics: Motion and Forces

Newton's Laws of Motion

1st Law: Law of Inertia

An object at rest stays at rest, and an object in motion stays in motion, unless acted upon by an unbalanced force.

Example: Seatbelt keeps you from flying forward when car stops.

2nd Law: F = ma

Force equals mass times acceleration.

More force = more acceleration; More mass = less acceleration (for same force)

3rd Law: Action-Reaction

For every action, there is an equal and opposite reaction.

Example: Rocket pushes gas down, gas pushes rocket up.

Motion Formulas

Speed = Distance / Time

Velocity = Displacement / Time

Acceleration = (v - u) / t

v = u + at

s = ut + Β½atΒ²

vΒ² = uΒ² + 2as

u = initial velocity, v = final velocity, a = acceleration, t = time, s = displacement

Work, Energy, and Power

ConceptFormulaUnit
WorkW = F Γ— d Γ— cos ΞΈJoule (J)
Kinetic EnergyKE = Β½mvΒ²Joule (J)
Potential EnergyPE = mghJoule (J)
PowerP = W / tWatt (W)

4. Earth Science: Plate Tectonics

Plate Tectonics Theory

Earth's lithosphere is divided into large plates that move on the asthenosphere due to convection currents in the mantle.

Types of Plate Boundaries

Divergent

Plates move apart

Creates: Mid-ocean ridges, rift valleys

Example: Mid-Atlantic Ridge

Convergent

Plates move toward each other

Creates: Mountains, trenches, volcanoes

Example: Himalayas, Philippine Trench

Transform

Plates slide past each other

Creates: Earthquakes

Example: San Andreas Fault

Earthquakes

  • Focus (Hypocenter): Point inside Earth where earthquake originates
  • Epicenter: Point on Earth's surface directly above focus
  • Seismic Waves: P-waves (fastest, compressional), S-waves (slower, shear), Surface waves (most destructive)
  • Richter Scale: Measures magnitude (energy released)

Volcanoes

Shield Volcano

Broad, gentle slopes (Hawaii)

Cinder Cone

Steep, small (Paricutin)

Stratovolcano

Tall, steep (Mt. Mayon, Mt. Pinatubo)

5. Ecology and Environment

Levels of Organization

Organism→Population→Community→Ecosystem→Biome→Biosphere

Food Chain and Energy Flow

Sun→Producers→Primary Consumers→Secondary Consumers→Tertiary Consumers

Only 10% of energy is transferred to the next level (10% Rule)

Biogeochemical Cycles

Water Cycle

Evaporation β†’ Condensation β†’ Precipitation β†’ Collection

Carbon Cycle

Photosynthesis (removes COβ‚‚), Respiration & Combustion (releases COβ‚‚)

Nitrogen Cycle

Nitrogen fixation by bacteria, used by plants, returned by decomposition

Oxygen Cycle

Produced by photosynthesis, consumed by respiration

Key Takeaways

  • βœ“Cell Theory: All living things are made of cells
  • βœ“DNA base pairs: A-T and G-C
  • βœ“Mitochondria = "Powerhouse" (produces ATP)
  • βœ“Newton's 2nd Law: F = ma
  • βœ“Ionic = transfer; Covalent = sharing electrons
  • βœ“Plate boundaries: Divergent, Convergent, Transform
  • βœ“Energy transfer: Only 10% to next trophic level
  • βœ“KE = Β½mvΒ²; PE = mgh
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