Biology 119 Exam 1 (2)

Organisms are composed of

matter

Essential Elements

Elements an organism needs to live and reproduce

Subatomic particles of an atom

Neutrons, Protons (+), and Electrons (-)

Atomic Nucleus composition

Protons and neutrons packed together

Ionic Bonds

Electrical attraction between atoms that gain or lose electrons

Cation

A positively charged ion (e.g., Na+)

Anion

A negatively charged ion (e.g., Cl-)

Covalent Bonds

Atoms sharing valence electrons; the strongest bond

Hydrogen Bonds

Weak attractions between Hydrogen and electronegative atoms (N, O, F)

Van der Waals Interactions

Weak forces that attract molecules and stabilize protein shape

Cohesion

The force keeping water molecules close together

Adhesion

The clinging of water molecules to another substance

Solvent

The dissolving agent of a solution

Solute

The substance that is dissolved

Aqueous solution

A solution in which water is the solvent

Four major classes of organic molecules

Carbohydrates, lipids, proteins, and nucleic acids

Carbohydrate C:H:O ratio

1C:2H:1O

Lipids

Water-insoluble molecules composed mostly of hydrocarbons

Fats composition

Glycerol and fatty acids

Phospholipids function

Form cell membranes

Steroids function

Serve as hormones to regulate cellular activities

Proteins

Polymers of amino acids that perform vital functions

Amino acid structure

Central carbon, amino group, carboxyl group, hydrogen, and R group

Peptide Bonds

Covalent bonds linking amino acids into polypeptides

DNA (deoxyribonucleic acid)

Stores hereditary information for all living organisms

Nucleotide components

Nitrogenous base, five-carbon sugar, and phosphate groups

DNA base pairs

Adenine-Thymine (A-T) and Cytosine-Guanine (C-G)

RNA base difference

Uracil takes the place of Thymine (A-U)

Kinetic energy

The energy of an object in motion

Potential energy

Stored energy

First Law of Thermodynamics

Energy cannot be created or destroyed, only transformed

Second Law of Thermodynamics

Total disorder (entropy) always increases

Catalyst

Chemical agent that accelerates a reaction without being changed

Enzymes

Specific proteins that lower activation energy to speed reactions

Cofactor

A non-protein group (like Mg or Fe) that binds to enzymes

Coenzyme

Small organic molecules (vitamins) that act as cofactors

Competitive inhibition

Inhibitor binds to the active site to block the substrate

Non-competitive inhibition

Inhibitor binds elsewhere to reduce active site ability

Cell Theory

All organisms are made of cells; cells are the basic unit; cells arise from division

Prokaryotes

Cells with no nucleus and no membrane-bound organelles

Eukaryotes

Cells with DNA in a nucleus and membrane-bound organelles

Plasma Membrane

Selectively permeable double layer of phospholipids

Cytoskeleton

Protein fibers and tubes that maintain cell shape and movement

Nucleus

Separated from cytoplasm by a double-membrane nuclear envelope

Ribosomes

Site of protein synthesis in the cytosol or on the ER

Rough ER

Studded with ribosomes; site of protein synthesis

Smooth ER

No ribosomes; synthesizes lipids and inactivates toxins

Golgi Apparatus

Flattened sacs that modify, sort, and package ER products

Lysosome

Vesicle with enzymes for intracellular digestion (autophagy)

Mitochondria

Double-membrane organelle that produces ATP via respiration

Chloroplast

Double-membrane organelle that produces sugar via photosynthesis

Endosymbiont Theory

Mitochondria/Chloroplasts originated as engulfed prokaryotic cells

Passive transport

Movement with the concentration gradient (no energy)

Active transport

Movement against the concentration gradient (requires energy/ATP)

Osmosis

Net diffusion of water across a selectively permeable membrane

Hypertonic solution

Higher solute concentration outside; causes water to leave the cell

Isotonic solution

Solute concentration is equal inside and outside the cell

Exocytosis

Fusion of a vesicle with the membrane to release contents

Phagocytosis

"Cell eating"; engulfing particles or microbes

NAD+ and NADH

Recyclable electron carriers used in redox reactions

Cellular Respiration

Process converting sugars, fats, and proteins into ATP

Pyruvate Oxidation

Pyruvate is converted to Acetyl-CoA in the mitochondria

Citric Acid Cycle (Krebs)

Eight reactions in the matrix that release CO2 and generate NADH/FADH2

Chemiosmosis

Movement of H+ ions down a gradient to build ATP

Aerobic respiration

Respiration occurring in the presence of Oxygen

Fermentation

Process using substrate-level phosphorylation instead of ETC to make ATP

Lactic acid fermentation

Pyruvate converted to lactate; occurs in animal muscle cells

Light-dependent reaction

Photosynthesis step producing ATP and NADPH

Light-independent reaction (Calvin Cycle)

Uses ATP and NADPH to convert CO2 to sugar

Photolysis of Water

Splitting water (H2O) to release electrons and Oxygen

C4 Pathway

Minimizes photorespiration using spatial separation

CAM Pathway

Minimizes water loss by absorbing CO2 at night (temporal separation)

Organisms are composed of

matter

Essential Elements

Elements an organism needs to live and reproduce

Subatomic particles of an atom

Neutrons, Protons (+), and Electrons (-)

Atomic Nucleus composition

Protons and neutrons packed together

Ionic Bonds

Electrical attraction between atoms that gain or lose electrons

Cation

A positively charged ion (e.g., Na+)

Anion

A negatively charged ion (e.g., Cl-)

Covalent Bonds

Atoms sharing valence electrons; the strongest bond

Hydrogen Bonds

Weak attractions between Hydrogen and electronegative atoms (N, O, F)

Van der Waals Interactions

Weak forces that attract molecules and stabilize protein shape

Cohesion

The force keeping water molecules close together

Adhesion

The clinging of water molecules to another substance

Solvent

The dissolving agent of a solution

Solute

The substance that is dissolved

Aqueous solution

A solution in which water is the solvent

Four major classes of organic molecules

Carbohydrates, lipids, proteins, and nucleic acids

Carbohydrate C:H:O ratio

1C:2H:1O

Lipids

Water-insoluble molecules composed mostly of hydrocarbons

Fats composition

Glycerol and fatty acids

Phospholipids function

Form cell membranes

Steroids function

Serve as hormones to regulate cellular activities

Proteins

Polymers of amino acids that perform vital functions

Amino acid structure

Central carbon, amino group, carboxyl group, hydrogen, and R group

Peptide Bonds

Covalent bonds linking amino acids into polypeptides

DNA (deoxyribonucleic acid)

Stores hereditary information for all living organisms

Nucleotide components

Nitrogenous base, five-carbon sugar, and phosphate groups

DNA base pairs

Adenine-Thymine (A-T) and Cytosine-Guanine (C-G)

RNA base difference

Uracil takes the place of Thymine (A-U)