Chapter 2 & 3 Chemistry & Biology Review - Vocabulary Flashcards

Vocabulary cards covering key concepts from the notes on Chapter 2 (Chemistry) and Chapter 3 (Biology & the Cell).

Element

A substance that cannot be broken down by ordinary chemical means; the periodic table lists elements.

Atom

The basic building block of matter; the smallest unit of an element, made of protons, neutrons, and electrons.

Proton

Positively charged subatomic particle located in the nucleus.

Neutron

Electrically neutral subatomic particle located in the nucleus.

Electron

Negatively charged subatomic particle orbiting the nucleus.

Ion

An atom with a net electric charge due to gain or loss of electrons.

Cation

A positively charged ion formed when an atom loses electrons.

Anion

A negatively charged ion formed when an atom gains electrons.

Major elements

Elements that make up about 96% of body mass.

Oxygen (O)

Major element essential for respiration; symbol O.

Carbon (C)

Major element forming the backbone of organic molecules.

Hydrogen (H)

Major element; most abundant in the body, mainly as H atoms.

Nitrogen (N)

Major element; component of amino acids and nucleic acids.

Lesser elements

Elements that make up about 3.9% of body mass.

Calcium (Ca)

Lesser element important for bones, muscles, and nerves.

Phosphorus (P)

Lesser element part of bones and ATP.

Potassium (K)

Lesser element; major intracellular cation.

Sulfur (S)

Lesser element; component of certain amino acids.

Sodium (Na)

Lesser element; major extracellular cation.

Chlorine (Cl)

Lesser element; essential anion.

Magnesium (Mg)

Lesser element; important cofactor.

Iodine (I)

Lesser element essential for thyroid hormones.

Iron (Fe)

Lesser element critical for oxygen transport and enzymes.

Trace elements

Chromium (Cr)

Trace element; cofactor in some enzymes.

Manganese (Mn)

Trace element; cofactor in enzymes.

Zinc (Zn)

Trace element; essential cofactor for many enzymes.

Inorganic compounds

Compounds that do not contain carbon-hydrogen bonds.

Organic compounds

Compounds that do contain carbon; include carbs, lipids, proteins, nucleic acids.

Water

Most important inorganic compound; 60–80% of cell volume.

Acids

Hydrogen ion donors (release H+ in solution).

Bases

Proton acceptors (take up H+ from solution).

pH

Measure of hydrogen ion concentration; scale 0–14 with 7 neutral.

Neutral

pH of 7; solution with equal H+ and OH−.

Isotonic

Solution with the same solute concentration as cytosol.

Hypertonic

Solution with greater solute concentration than cytosol.

Hypotonic

Solution with lower solute concentration than cytosol.

Carbohydrates

Carbon-containing compounds; major cellular fuel; includes sugars and starches.

Monosaccharides

Simple sugars (one sugar unit).

Disaccharides

Two monosaccharides linked together (double sugars).

Sucrose

Disaccharide composed of glucose and fructose.

Maltose

Disaccharide composed of two glucose molecules.

Lactose

Disaccharide composed of glucose and galactose.

Polysaccharides

Long chains of monosaccharides (starch, glycogen).

Glycogen

Polysaccharide; stored glucose in animals.

Lipids

Fats and oils; include triglycerides, phospholipids, and steroids.

Phospholipids

Lipids that make up cell membranes.

Proteins

Polymers of amino acids; many function as enzymes.

Enzymes

Biological catalysts that lower activation energy of reactions.

Peptide bond

Bond linking amino acids in a protein.

Nucleic acids

DNA and RNA; store and express genetic information.

DNA

Deoxyribonucleic acid; stores genetic information.

RNA

Ribonucleic acid; coordinates protein synthesis.

ATP

Adenosine triphosphate; cellular energy currency with high-energy phosphate bonds.

Na+-K+ pump

Sodium-potassium ATPase; maintains ion gradients across the membrane.

Primary active transport

Energy-driven transport moving solutes against their gradient using ATP.

Secondary active transport

Uses ion gradients (from primary pump) to drive transport of other solutes.

Diffusion

Movement of particles down their concentration gradient.

Osmosis

Diffusion of water across a semipermeable membrane.

Facilitated diffusion

Carrier- or channel-mediated transport without ATP.

Plasma membrane

Phospholipid bilayer that encloses the cell and separates ICF from ECF.

Integral proteins

Membrane proteins embedded within the lipid bilayer.

Peripheral proteins

Membrane proteins attached to the surface of the membrane.

Glycocalyx

Carbohydrate-rich surface on the external side of the plasma membrane.

Tight junction

Impermeable junction preventing fluid/molecule leakage between cells.

Desmosome

Anchoring junction that binds cells together under tension.

Gap junction

Communicating junction allowing ions/mmall molecules to pass between cells.

Mitochondria

Powerhouse of the cell; site of most ATP production.

Nucleus

Genetic control center; houses DNA and nucleolus; controls cell activities.

Nuclear envelope

Double membrane around the nucleus with pores; continuous with RER.

Nucleolus

Dense region within the nucleus where rRNA synthesis occurs.

Chromatin

DNA wrapped around histone proteins; condenses into chromosomes during division.

Chromosome

Condensed chromatin visible during cell division.

Cytoplasm

Region between the plasma membrane and nucleus; contains cytosol and organelles.

Cytosol

Fluid component of cytoplasm with dissolved solutes.

Ribosomes

Sites of protein synthesis; may be free-floating or attached to RER.

Endomembrane system

Network of membranes involved in synthesis, modification, and transport of biomolecules.