Semester 1 Exam Review

Atom

Smallest unit of matter containing protons, neutrons, and electrons

Element

Pure substance made of one type of atom

Molecule

Two or more atoms bonded together

Compound

A molecule made of different elements

Ionic Bond

Bond formed by transfer of electrons

Covalent Bond

Bond formed by sharing electrons

Hydrogen Bond

Weak attraction between polar molecules

Monomer

Small building block molecule

Polymer

Chain of monomers

Carbohydrate

Organic molecule for quick energy; made of C, H, O

Monosaccharide

Single sugar molecule

Polysaccharide

Long chain of sugar molecules

Simple Carbohydrate

Quick energy, breaks down fast (glucose)

Complex Carbohydrate

Long term energy, slower digestion (starch)

Soluble Fiber

Dissolves in water; slows digestion

Insoluble Fiber

Helps movement through digestive tract

Protein 

Organic molecule made of amino acids used for structure and enzymes

Amino Acid

Monomer of proteins

Lipid

Organic molecule used for long term energy storage

Fatty Acid

Monomer of lipids

Saturated Fat

Solid at room temperature; no double bonds

Unsaturated Fat

Liquid at room temperature; has double bonds

Trans Fat

Artificially hydrogenated fat; unhealthy

Nucleic Acid

DNA or RNA; stores genetic information

Nucleotide

Monomer of nucleic acids

Acid

pH below 7

Base

pH above 7

Neutral

pH of 7

Enzyme

Protein catalyst that speeds up reactions

Active Site

Region where substrate binds

Denature

Enzyme loses shape and function

Characteristics of Life

Eight traits that define living organisms

Biotic

Living components of an ecosystem

Abiotic

Nonliving components of an ecosystem

Free Energy

Energy available to do work

Chemical Energy

Energy stored in molecular bonds

Energy Flow 

One way movement of energy through an ecosystem

Metabolism

All chemical reactions in an organism

Digestive System

System that breaks down and absorbs nutrients

Mouth

Begins mechanical and chemical digestion

Esophagus

Uses peristalsis to move food

Stomach

Digests proteins with acid and enzymes

Small Intestine

Where most digestion and nutrient absorption occurs

Large Intestine

Absorbs water and forms feces

Diffusion

Movement of molecules high → low concentration

Osmosis

Diffusion of water

Facilitated Diffusion

Passive transport using membrane proteins

Active Transport 

Movement against gradient using ATP

Endocytosis

Cell taking in materials

Exocytosis

Cell expelling materials

Phagocytosis

Cell eating solids

Pinocytosis

Cell drinking liquids

Phospholipid Bilayer

Structure of the cell membrane

Selective Permeability

Only certain substances can cross the membrane

Prokaryote

Simple cell without nucleus

Eukaryote

Complex cell with nucleus

Cell Theory

All living things are made of cells, cells come from cells, cells are basic unit of life

Photosynthesis

Converts light energy to chemical energy (glucose)

Photosynthesis Formula

6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂

Chloroplast

Organelle where photosynthesis occurs

Chlorophyll 

Pigment that absorbs light

Thylakoid

Site of light dependent reactions

Stroma

Site of Calvin Cycle

PSII

Splits water during light reactions

PSI

Re Energizes electrons during light reactions (excites them)

Electron Transport Chain 

Makes ATP during light reactions

ATP

Main energy molecule of cells

NADPH

Electron carrier used in Calvin Cycle

Calvin Cycle

Makes glucose using ATP and NADPH

C3 Plant

Normal plant type

C4 Plant

Hot climate plant type

CAM Plant

Desert plant that opens stomata at night

Cellular Respiration

Converts glucose to ATP

Respiration Formula

C₆H₁₂O₆ + O₂ → CO₂ + H₂O + ATP

Aerobic Respiration

Uses oxygen, produces ~36 ATP

Anaerobic Respiration

No oxygen, produces 2 ATP

Fermentation

Anaerobic process producing lactic acid or alcohol

Lactic Acid Fermentation

Occurs in muscles without oxygen

Alcoholic Fermentation

Occurs in yeast

Glycolysis

First step of respiration; breaks glucose into pyruvate

Pyruvate

Product of glycolysis

Krebs Cycle

Produces CO₂, NADH, FADH₂

ETC

Produces the most ATP using oxygen

NADH

Electron carrier

FADH₂

Electron carrier

Mitochondria

Organelle where respiration occurs

Cell Cycle 

Life cycle of a cell

Interphase

G1, S, G2 phases where cell grows and copies DNA

Mitosis

The process of cell division where a single cell divides into two genetically identical daughter cells, maintaining the chromosome number

Prophase

Chromosomes condense; spindle forms

Metaphase

Chromosomes line up in the center

Anaphase

Sister chromatids pulled apart

Telophase

Two nuclei form

Cytokinesis

Cell splits into two daughter cells

Meiosis

Cell division producing 4 genetically different haploid gametes

Crossing Over

Exchange of DNA in Prophase I

Independent Assortment

Random mixing of chromosomes

Haploid

Half the chromosome number

Diploid

Full chromosome number

Checkpoint

Control mechanism preventing damaged cells from dividing