Biology Chapter on Atoms and Molecules

A substance that cannot be broken down by chemical means.

The six key elements in living organisms: Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur.

The smallest piece of an element that retains its properties.

A positively charged particle found in the nucleus of an atom, weighing 1 amu.

A neutral particle in the nucleus of an atom, also weighing 1 amu.

Total number of protons and neutrons in an atom's nucleus.

Same element with different weights due to varying numbers of neutrons.

Atoms with different charges due to differing numbers of electrons.

Life must possess five key characteristics: organization, energy requirement, homeostasis, reproduction, and evolution.

The cell is the fundamental unit of life, forming tissues, organs, and organisms.

Characteristics that arise when components work together as a system, surpassing the sum of individual parts.

Organisms, mainly plants, that produce their own food using sunlight, carbon dioxide, and water.

Organisms that obtain energy by eating other organisms, categorized as heterotrophs.

Heterotrophs that break down dead organisms and recycle nutrients back into the environment.

The process through which living organisms maintain a stable internal environment despite external changes.

The process where environmental factors favor the survival of organisms with advantageous traits over generations.

The science of classifying organisms based on evolutionary relationships.

A single-celled organism without a nuclear membrane or membrane-bound organelles.

An organism with a membrane-bound nucleus and organelles.

The three classifications of life: Bacteria, Archaea, and Eukarya.

The transfer of genetic material between organisms not through parent-offspring.

Asexual reproduction where a single organism divides into two identical organisms.

The domain that includes all eukaryotic organisms, both unicellular and multicellular.

A kingdom within Domain Eukarya that includes unicellular and multicellular organisms.

Multicellular or unicellular heterotrophs that absorb their food.

Multicellular heterotrophs that ingest their food.

Multicellular autotrophs that produce their own energy.

A tentative explanation for an observation, must be testable.

The variable manipulated by the scientist to test its effect.

The variable measured in an experiment, affected by the independent variable.

The process where other scientists evaluate research before publication.

Basic research expands knowledge; applied research solves real problems.

Substances that do not dissolve in water due to nonpolar bonds.

Bonds that allow water to resist temperature changes due to its unique structure.

Ice has a lower density than liquid water due to its hexagonal structure when frozen.

A scale measuring H+ ion concentration, indicating acidity or alkalinity of solutions.

A strong acid with a pH of 1 that contributes H+ to solutions.

A strong base with a pH of 14 that absorbs H+ from solutions.

Process of linking monomers by removing water to form polymers.

Four structure levels: Primary, Secondary, Tertiary, and Quaternary, defining a protein’s shape.

A strong bond formed by shared electrons between atoms.

A bond where electrons are shared unevenly, creating partial charges.

A weak bond formed between molecules with opposite partial charges.

A strong bond formed when one atom completely transfers an electron to another.

An element's ability to attract electrons toward itself.

The tendency of water molecules to stick together.

The ability of water molecules to form bonds with different substances.

Water's ability to dissolve hydrophilic ('water-loving') substances.