Science notes

What is the smallest functional unit of life?

A cell.

What are the four types of tissues in the body?

Epithelial, connective, muscle, and nerve.

What is the function of epithelial tissue?

Forms the skin.

What is chemical digestion?

The process where the body uses chemicals to break down food.

What are the two processes involved in digestion?

Mechanical digestion and chemical digestion.

What is the primary function of the respiratory system?

Responsible for breathing.

What is the role of alveoli in the respiratory system?

They act as the primary site for gas exchange.

What does the circulatory system transport?

Oxygen and products to cells.

What is the function of the nephrons in the excretory system?

Help maintain blood pressure and pH balance in the kidney.

What are the four major organs of a plant?

Roots, leaves, stem, and reproductive structures.

What is photosynthesis?

The process of converting carbon dioxide and water into oxygen and glucose using sunlight.

What are the two types of roots in plants?

Tap roots and fibrous roots.

What is osmosis?

The process of water absorption in root hairs.

What is the definition of an ecosystem?

A group of abiotic and biotic things that interact with one another.

What is the Law of the Conservation of Energy?

States that energy cannot be created or destroyed.

What is the structure of the Earth?

Inner core, outer core, mantle, and crust.

What are the three types of rocks?

Igneous, sedimentary, and metamorphic rocks.

What is the definition of a mineral?

A pure, naturally occurring solid with a fixed chemical structure.

What is the purpose of a scientific report?

To systematically present research findings.

What is an independent variable?

The variable that is changed in an experiment.

What is a dependent variable?

The variable that is measured in an experiment.

What is validity in scientific experiments?

The extent to which a variable measures what it is supposed to measure.

Define reliability in the context of experiments.

The degree to which an experiment's results can be repeated.

What are body fossils?

The remains of an organism’s body.

What is an alloy?

A mixture of metals.

What are the levels of organisation in living organisms, from simplest to most complex?

Cell → Tissue → Organ → Organ systems → Organism (cells group to form tissues, tissues form organs, and organs combine to form organ systems).