Bio 101 Test 1

Element

A substance composed of atoms that cannot be broken down into simpler substances.

Atom

The smallest unit of matter that retains all chemical properties of an element.

Subatomic Particles

Proton (+) (1 amu), Neutron (neutral)(1 amu), Electron (-)(5.4x10^-4 amu).

Atomic Number

Tells us the number of protons in an atom.

Atomic Weight

Tells us the number of protons and neutrons in an atom.

Isotope

Atoms with the same number of protons but different numbers of neutrons.

Radioactive Isotope

Atoms that contain an unstable combination of neutrons and protons.

Molecule

A group of two or more atoms connected by chemical bonds.

Covalent Bond

Strong attraction between two atoms through shared electrons.

Ion

An atom that has gained or lost electrons.

Ionic Bond

Attraction between two atoms/molecules due to their charge.

Charge on an Ion

Determined by subtracting the number of electrons from the number of protons.

Hydrogen Bond

Weak attraction between partial charges on molecules.

Solvent

The substance that dissolves a solute to produce a solution.

Solute

The substance that is dissolved in a solvent to produce a solution.

Solution

A homogeneous mixture of one or more solutes dissolved in a solvent.

Surface Tension

Property of a liquid's surface that allows it to resist external force due to cohesion.

Capillary Action

Liquid flow through narrow spaces without external forces, aided by cohesion and adhesion.

Cohesion

The ability of water molecules to attract other water molecules due to hydrogen bonding.

pH

A figure expressing acidity on a logarithmic scale, with 7 being neutral.

Buffer

A solution that resists pH change upon the addition of an acidic or basic component.

Hydrophobic

Tending to fail to mix with water.

Hydrophilic

Tending to mix with water.

Carbon

The basic element of living things due to its ability to form stable bonds with many elements.

Functional Groups

Specific groups of atoms within molecules that determine the characteristics of those molecules.

Carbohydrates

Biomolecules made of monomeric units, serving as energy storage and structure.

Lipids

Biomolecules not made of monomeric units, providing insulation and energy storage.

Proteins

Biomolecules not made of monomeric units, functioning in catalysis, structure, and transport.

Nucleic Acids

Biomolecules made of monomeric units, responsible for genetic information and protein synthesis.

Monosaccharides

Simple sugars like glucose, fructose, and galactose.

Disaccharides

Sugars made of two monosaccharides, such as sucrose, lactose, and maltose.

Glycogen

A storage form of polysaccharide.

Cellulose

A polysaccharide with a structural function.

Phospholipids

Lipids with a hydrophilic phosphate group and two hydrophobic fatty acid chains.

Triglycerides

Lipids that are solid at room temperature.

Eukaryote

Organism with cells containing a distinct nucleus and membrane-bound organelles.

Prokaryote

Single-celled organism lacking a nucleus or membrane-bound organelles.

Domains of Life

Bacteria, Archaea, and Eukarya.

Nucleus

Contains DNA within a cell.

Rough Endoplasmic Reticulum

Site of protein synthesis.

Smooth Endoplasmic Reticulum

Involved in lipid and carbohydrate synthesis.

Golgi Apparatus

Modifies and packages materials from the ER.

Ribosome

Site of protein synthesis.

Lysosome

Digests macromolecules.

Plasma Membrane

Boundary of the cell.

Cytosol

Gel-like fluid within the cell.

Mitochondria

Produces ATP.

Peroxisome

Detoxifies peroxides.

Plant Cell Structures

Cell wall, chloroplasts, vacuoles, and plasmodesmata.