Interactions over Small and Large Distances

Gravitational Force

Electromagnetic Force

Nuclear Forces

Types of Forces

Gravitational Force

The force of attraction between two masses

Electromagnetic Force

The force between charged particles

Nuclear Forces

Forces that act within the nucleus of an atom.

Strong Nuclear Force

The force that holds protons and neutrons together in the nucleus

Strong Nuclear Force, Weak Nuclear Force

Types of Nuclear Forces

Weak Nuclear Force

Responsible for radioactive decay processes.

Contact Forces

Forces that occur when objects are physically touching

Friction, Tension, Normal Force

Contact Forces

Friction

The force that opposes the motion of objects in contact

Tension

The force transmitted through a string, rope, or wire when it is pulled tight

Normal Force

The support force exerted upon an object in contact with another stable object

Non-Contact Forces

Forces that act over a distance without physical contact

Gravitational Force, Magnetic Force, Electrostatic Force

Non-Contact Forces

Magnetic Force

Attraction or repulsion between magnetic poles

Electrostatic Force

Attraction or repulsion between charged particles.

Atomic and Subatomic Interactions

Biological Interactions at the Cellular Level

Small-Scale Interactions

Atomic Structure

Intermolecular Forces

Chemical Bonds

Atomic and Subatomic Interactions

Atomic Structure

Atoms consist of a nucleus (protons and neutrons) surrounded by electrons.

Electron Clouds: Regions where electrons are likely to be found.

Example: Hydrogen atom, with one proton and one electron.

Intermolecular Forces

Forces between molecules

Chemical Bonds

Forces holding atoms together in molecules.

Van der Waals Forces, Dipole-Dipole Interactions, Hydrogen Bonds

Intermolecular Forces

Van der Waals Forces

Weak attractions between molecules

Dipole-Dipole Interactions

Attraction between polar molecules

Hydrogen Bonds

Strong dipole-dipole interactions involving hydrogen

Ionic Bonds, Covalent Bonds, Metallic Bonds

Chemical Bonds types

Ionic Bonds

Transfer of electrons from one atom to another

Covalent Bonds

Sharing of electrons between atoms

Metallic Bonds

Electrons are shared in a 'sea' of electrons around metal atoms

Cell Membrane Interactions

How substances move in and out of cells

Diffusion, Osmosis, Active Transport

Cell Membrane Interactions types

Diffusion

Movement of molecules from high to low concentration

Osmosis

Diffusion of water across a semi-permeable membrane

Active Transport

Movement of molecules against a concentration gradient using energy

Cell Communication

How cells interact and communicate

Signal Transduction,

Cell Communication types

Signal Transduction

Process by which a chemical or physical signal is transmitted through a cell.

Enzyme Activity

How enzymes catalyze biochemical reactions

Enzyme-Substrate Interaction

Lock and Key Model

Induced Fit Model

Enzyme Activity types

Enzyme-Substrate Interaction

The specific binding of an enzyme to its substrate

Lock and Key Model

The enzyme’s active site is a perfect fit for the substrate

Induced Fit Model

The enzyme changes shape slightly to accommodate the substrate.

Gravitational Interactions in Astronomy

Electromagnetic Interactions

Biological Interactions in Ecosystems

Large-Scale Interactions

Planetary Orbits, Tidal Forces, Black Holes

Gravitational Interactions in Astronomy

Planetary Orbits

How planets orbit stars due to gravitational forces

Kepler's Laws of Planetary Motion

• First Law: Planets orbit in ellipses with the Sun at one focus.

• Second Law: A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.

• Third Law: The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.

Tidal Forces

The gravitational pull of the moon and the sun on Earth’s oceans

Spring Tides, Neap Tides

Tidal Forces types

Spring Tides

Higher tides when the Earth, moon, and sun are aligned

Neap Tides

Lower tides when the Earth, moon, and sun form a right angle

Black Holes

Regions of space where gravity is so strong that not even light can escape

Formation

Result from the collapse of massive stars

Event Horizon

The boundary beyond which nothing can escape

Electromagnetic Spectrum

Light and Optics

Electricity and Magnetism

Electromagnetic Interactions

Electromagnetic Spectrum

Range of all types of electromagnetic radiation.

Light and Optics

How light interacts with different media

Electricity and Magnetism

Interaction between electric currents and magnetic fields

Radio Waves, Microwaves, Infrared, Visible Light, Ultraviolet, X-Rays, Gamma Rays

types of electromagnetic radiation

Radio Waves

Used in communication

Microwaves

Used in cooking and satellite transmissions

Infrared

Heat radiation

Visible Light

The light we can see

Ultraviolet

Can cause sunburn

X-Rays

Used in medical imaging

Gamma Rays

High energy radiation from radioactive decay

Reflection

Bouncing of light off a surface

Refraction

Bending of light as it passes from one medium to another.

Diffraction

Spreading of light waves around obstacles

Interference

When two waves overlap and combine

Electromagnetic Induction

Generating an electric current by changing a magnetic field

Faraday's Law

The induced electromotive force in any closed circuit is equal to the rate of change of the magnetic flux through the circuit

Food Chains and Webs, Symbiotic Relationships, Population Dynamics, Ecological Succession

Biological Interactions in Ecosystems

Food Chains and Webs

 How energy and nutrients flow through an ecosystem

Symbiotic Relationships

Interactions between different species

Population Dynamics

Changes in population sizes and composition over time

Ecological Succession

The process by which the structure of a biological community evolves over time

Producers

Organisms that produce their own food (e.g., plants).

Consumers

Organisms that consume other organisms for energy

Decomposers

Organisms that break down dead material for energy

Mutualism

Both species benefit

Commensalism

One species benefits, the other is neither helped nor harmed

Parasitism

One species benefits at the expense of the other.

Carrying Capacity

The maximum population size that an environment can support

Factors Affecting Populations

Birth rates, death rates, immigration, and emigration

Primary Succession

Occurs in lifeless areas where there is no soil.

Secondary Succession

Occurs in areas where a community has been disturbed but soil remains