Science 9

Mitosis is the process through which a pre-existing cell makes two genetically identical copies of itself.

Meiosis is the process through which sex cells (eggs and sperm) are formed by a parent cell dividing twice, resulting in four daughter cells.

Mitosis is how organisms grow (adding new cells) and repair damaged tissue (like healing a cut), not just how they reproduce.

Each of the four daughter cells from meiosis carries only HALF the genetic information of the original parent cell — unlike mitosis, which keeps the full amount.

The two resulting daughter cells each carry the exact same genetic information as the original parent cell.

The periodic table groups elements according to their atomic number and shared properties, such as atomic size, whether they're a metal, non-metal, or semi-metal (metalloid), and their chemical family.

An ionic compound forms when electrons are TRANSFERRED from a metal to a non-metal, creating charged ions that attract each other (e.g. sodium chloride, table salt).

Elements in the same column (group) tend to share similar chemical behaviour; some elements, like hydrogen, nitrogen, and oxygen, exist as diatomic elements (pairs of atoms bonded together).

A covalent compound forms when electrons are SHARED between two non-metals, rather than transferred (e.g. water, carbon dioxide).

Reading across a row or down a column of the periodic table reveals repeating patterns, which is why it's called 'periodic'.

A circuit's basic components are a power source, a load or resistor (like a lightbulb), a conductor, and a switch — connected in an unbroken loop.

Voltage is the electrical push (or 'pressure') that drives electrons through a circuit, measured in volts.

Electrons only flow around a circuit if the loop is complete; a break anywhere — like an open switch, a disconnected wire, or a burnt-out bulb — stops the current everywhere in that loop.

Higher-voltage sources carry greater relative danger — this is why household wiring and high-voltage power lines carry strong safety warnings.

Current is the flow of electric charge (electrons) through a circuit, measured in amps (amperes).

Solar radiation provides the energy required for most life on Earth and is the root cause of wind and ocean currents, which distribute energy and nutrients around the planet.

Matter cycles within the biotic (living, like plants, animals, decomposers) and abiotic (non-living, like air, water, soil) components of an ecosystem — examples include the water, nitrogen, carbon, and phosphorus cycles.

A systems approach to sustainability sees all matter and energy as interconnected and existing in dynamic equilibrium — balanced, not static.

Interconnectedness means everything is connected, from local to global — First Peoples perspectives hold detailed knowledge of how living and non-living things depend on one another.

Solar radiation is also the energy source for the water cycle (evaporation) — connecting the sun's energy to matter moving between Earth's spheres.