Exam 1 BIO1200

Element

a pure substance of one kind of atom

Atoms

the smallest functional unit of matter

Proton

positive charge, found in nucleus

Neutrons

no charge, found in nucleus

Electrons

negative charge, arranged in orbitals around the nucleus

Atomic number represents

number of protons in an element

atomic mass

number of protons and neutrons

electronegativity

the ability of an atom to attract electrons

Ions

atoms that have gained or lost an electron

Molecules

made of two or more atoms that are connected by bonds

Ionic bond

bond between positive charged ion and negative charged ion

Covalent bonds

electrons are shared between two atoms

Covalent single bond

one pair of electrons is shared between two atoms

Covalent double bond

two pairs of electrons shared

Covalent triple bond

three pairs of electrons shared

Disulfide bond

single bond between two sulfur atoms

non-polar covalent bond

electrons are shared evenly between two atoms

polar covalent bond

electrons are unevenly shared between two atoms

Hydrogen bonds

formed when a hydrogen atom is electrically attached to an electronegative atom (O or N). easiest bond to break

cohesion

water molecules are attracted to other water molecules. they make H bonds

adhesion

water molecules are attracted to charged surfaces

Acid

a substance that releases H+ ions into the water when dissolved

Strong acid

completely dissociated into its ions ex. HCl to H+ and Cl-

Weak acid

partially dissociates into its ions; some stays in neutral form

Base

a substance that releases OH- ions when it dissolves in water

Strong base

completely dissociated into its ions

Weak base

partially dissociates in water

organic compounds

contain both hydrogen and carbon in the same molecule

Inorganic compounds

contain many different elements, metals, and ions

Macroelements

CHONPS; main components of macromolecules needed in large quantities

Microelements

Mg, K, Mn, Ca, Fe, Cu

elements needed in much smaller amounts

Covalent Bonds

electrons shared between two atoms

Disulfide Bonds

Covalent bond between two sulfur atoms

Ionic bonds

bond between + and - charged atoms

Hydrogen bond

Bond between hydrogen and an electronegative atom (O or N)

Hydroxyl group

-OH

Carbonyl group

-C=O

Carboxyl group

-COOH

Amino group

-NH2

Sulfhydryl group

-SH

Phosphate group

-PO4

Sulfate group

-SO4

Methyl group

-CH3

Dehydration synthesis reaction

connects subunits together to make a longer polymer (removes H2O)

Hydrolysis reaction

breaks a large polymer into smaller subunits (adds H2O)

Carbohydrates general formula

CH2O

Monosaccharides

simple sugars (one)

Disaccharides

two sugars connected by covalent bonds

polysaccharides 

long chains of sugar subunits

Functions of carbohydrates

food/energy, storage, structure

Lipids general structure

CHO

Proteins general structure

CHONS

Nucleic acid general structure

CHONP

Structural polysaccharide

has beta glycosidic bond. Can’t be broken down and is used to build structure

Cell theory

the cell is the smallest unit of life, all living things are made of cells, and every cell comes from a preexisting cell.

All cells contain:

Plasma membrane, cytoplasm, ribosomes, and DNA

Characteristics of Prokaryotes

no nucleus, DNA arranged in circular double stranded piece, no membrane bound organelles, small ribosomes, reproduced by fission

Characteristics of Eukaryotes

nucleus; linear DNA arranged in chromosomes; many membrane bound organelles; large ribosomes; reproduced by fission, asexual, or sexual reproduction

Plasma membrane function

regulates energy in and out of the cell

Plasma membrane structure

phospholipid bilayer with proteins attached and embedded in it.

Nucleus function

stores DNA, DNA replication, RNA synthesis

Mitochondrion function

cellular respiration, energy factory

Chloroplast function

photosynthesis, make sugar

Endosymbiont Theory

mitochondria and chloroplasts are derived from small bacteria that were engulfed by larger bacteria during the evolution of eukaryotic cells

Vacuole function

storage and breakdown of substances, turbot pressure in plants.

Perioxisomes

break down peroxide

Lysosomes

contains digestive enzymes that can break down macromolecules nutrients and cell parts so they can be used in the cell

Ribosomes function

protein synthesis

Endomembrane system

SER, RER, Golgi, vesicles

Rough ER function

protein synthesis, insertion of protein into membrane, glycosylation

Smooth ER function

lipid and membrane synthesis

Golgi function

packing and shipping center.

1. Proteins are received from the RER

2. Proteins are modified (glycosylation)

3. Proteins are sorted, packed into vesicles, and sent to final location in the cell

Vesicles

small membrane sacs that transport substances between membranes

Intracellular Transport steps

1. proteins are made in RER and packaged into vesicles

2. sent to the Golgi where they are glycosylated

3. packaged into new vesicles and sent to final destination

Cytoskeleton structure

network of molecules inside the cells. composed of actin microfilaments, intermediate filaments, and microtubules.

Cytoskeleton function

gives structure to the cell and organelles. involved in intracellular transport and cell movement

Actin microfilaments

located directly below the PM, gives shape, involved in cell movement

intermediate filaments

inside of cell, form general scaffold

microtubules

hollow tubes involved in intracellular movement. Is a component of flagella

Cilia and Flagella function

helps movement of a cell through liquid and across surfaces

Plasma membrane structure

lipid bilayer, cholesterol, proteins

glycoproteins

proteins with sugars covalently attached

function of the plasma membrane

compartmentation, communication, transport, seperating the living cell from outside environment

differentially permeable (semipermeable)

only certain molecules can enter the membrane

molecules that CAN pass through lipid bilayer

small, uncharged molecules; hydrophobic molecules

molecules that CANT pass through lipid bilayer

charged ions, large macromolecules, polar organic molecules

Diffusion

substance moves from higher concentration to lower concentration. movement is down the concentration gradient. no energy needed

Osmosis

the diffusion of water. water moves from a high concentration of water to a lower concentration of water. no energy needed.

Simple diffusion

solute moves from high to low concentration

no transport protein

no energy needed

Facilitated diffusion

solute moves from high to low concentation

uses transport protein

no energy needed

Direct active transport

at least one chemical is moving low to high

uses ATP

indirect active transport

two part system. one chemical moves low to high

ion moves high to low

energy used

uniport

one chemical transported

symport

two chemicals transported in the same direction

antiport

two chemicals transported in opposite directions

Exocytosis

brings substances out of the cell

Endocytosis

brings substances into the cell

ATP

adenosine triphosphate