Biolog 111- Exam 3

Alcohol Fermentation

a biological process by which sugar is converted into alcohol and carbon dioxide

amino acids

building blocks of proteins (monomers)

amphipathic

A molecule that has both a hydrophilic region and a hydrophobic region.

anabloic

complex molecules made from simple

ATP

(adenosine triphosphate) main energy source that cells use for most of their work

ATP synthase

the enzyme that makes ATP molecules (a protein)

Autotroph

an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide.

Carbohydrates

(Monosaccharride: Monomer) Polymer: Polysaccharide) Bond between: glycosidie linkage

Catabolism

Metabolic pathways that break down molecules, releasing energy.

Catalyst

chemical agent that speeds up the rate of a chemical reaction by lowering the activation energy (Ea) without itsself being consumed or modified In the reaction

cell wall

strong, supporting layer around the cell membrane in some cells

cellular respiration

Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen

Cellulose

A substance (made of sugars) that is common in the cell walls of many organisms

chemical energy

A form of potential energy that is stored in chemical bonds between atoms.

Chemiosmosis

the movement of ions across a semipermeable membrane

chlorophyll

Green pigment in plants that absorbs light energy used to carry out photosynthesis

Chloroplast

An organelle found in plant and algae cells where photosynthesis occurs

Cholesterol

steroid family of lipids

Chromatin

Clusters of DNA, RNA, and proteins in the nucleus of a cell

cytosine

A component of nucleic acids that carries hereditary information in DNA and RNA in cells. Chemically, it is a pyrimidine base.

Deoxyribose

A five-carbon sugar that is a component of DNA nucleotides

Desmosomes

Anchoring junctions that prevent cells from being pulled apart

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration.

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

electrochemcial gradient

The diffusion gradient of an ion, which is affected by both the concentration difference of an ion across a membrane (a chemical force) and the ion's tendency to move relative to the membrane potential (an electrical force).

electron transport chain

A sequence of electron carrier molecules (membrane proteins) that shuttle electrons during the redox reactions that release energy used to make ATP.

Endergonic

A chemical reaction that requires the input of energy in order to proceed.

Endocytosis

process by which a cell takes material into the cell by infolding of the cell membrane

Endoplasmic Reticulum

A cell structure that forms a maze of passageways in which proteins and other materials are carried from one part of the cell to another.

energy coupling

The use of an exergonic process to drive an endergonic one.

Enzyme

A type of protein that speeds up a chemical reaction in a living thing

eukarote

Organism whose cells have a nucleus and organelles

Exergonic

Chemical reactions that release energy

Exocytosis

Process by which a cell releases large amounts of material

facilitated diffusion

Movement of specific molecules across cell membranes through protein channels

FADH2

redox cofactor that is created during the Krebs cycle, last part of respiration

Fatty acid

hydrocarbon chain often bonded to glycerol in a lipid

Fermentation

Process by which cells release energy in the absence of oxygen

flagella+what does it do

hair like,assist the cell in movement. This includes certain bacteria like sperm

fluid mosaic

model of a cell membrane as a two-dimensional fluid of mixed composition

glcosidic linkage

A covalent bond formed between two monosaccharides by a dehydration reaction.

glycosylation

Addition of a carbohydrate group to a molecule.

heat

thermal energy in transfer from one body of matter to another (kinetic energy)

Heterotroph

An organism that cannot make its own food.

histone

protein that organizes chromosomes and around which DNA wraps

Hydrolysis

Breaking down complex molecules by the chemical addition of water

Hypertonic

when comparing two solutions, the solution with the greater concentration of solutes

hypotonic

Having a lower concentration of solute than another solution

inner membrane

The membrane of the mitochondria that is the site of electron transport and chemiosmosis.

integral proteins

penetrate the hydrophobic interior of the lipid bilayer

intermediate filaments

Threadlike proteins in the cell's cytoskeleton that are roughly twice as thick as microfilaments

inner membrane space

space between the inner and outer membrane of the mitochondria

Isotonic

Describes a solution whose solute concentration is equal to the solute concentration inside a cell

kinetic energy

energy of motion

Krebs cycle

second stage of cellular respiration, in which pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions (citric acid cycle)

Lactic acid

product of fermentation in many types of cells, including human muscle cells

lipid

Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.

lipid membrane

a compound which belongs to a group of (structurally similar to fats and oils) which form the double-layered surface of all cells (lipid bilayer). The three major classes of membrane lipids are phospholipids, glycolipids, and cholesterol

Lysosome

An organelle containing digestive enzymes

macromolecule

A very large organic molecule composed of many smaller molecules

Microtubules

Spiral strands of protein molecules that form a tubelike structure

Mitochondria

Powerhouse of the cell, organelle that is the site of ATP (energy) production

Monomer

A simple compound whose molecules can join together to form polymers

nucleotide

monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base

nucleus

A part of the cell containing DNA and RNA and responsible for growth and reproduction

organelle

specialized structure that performs important cellular functions within a eukaryotic cell

Osmosis

Diffusion of water through a selectively permeable membrane

outer membrane

The outer membrane is the outermost membrane in the mitochondria that protects and holds the form of the organelle.

oxaloacetate

A four-carbon molecule that binds with the two-carbon acetyl unit of acetyl-CoA to form citric acid in the first step of the Krebs cycle.

oxidation

The loss of electrons from a substance involved in a redox reaction.

peptide bond

The chemical bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid

peptidoglycan

A protein-carbohydrate compound that makes the cell walls of bacteria rigid

peripheral proteins

The proteins of a membrane that are not embedded in the lipid bilayer; they are appendages loosely bound to the surface of the membrane.

peroxisome

organelle with various specialized metabolic functions; produces hydrogen peroxide as a by-product, then converts it to water

phagocytosis

Cell eating

phospodiester bond

the linkage between the 3' carbon atom of one sugar molecule and the 5' carbon atom of another, deoxyribose in DNA and ribose in RNA

phospholipid

a lipid that contains phosphorus and that is a structural component in cell membranes

Pinocytosis

Cell drinking

Plasmodesmata

channels through cell walls that connect the cytoplasms of adjacent cells

plasmolysis

Collapse of a walled cell's cytoplasm due to a lack of water

Polymer

A long molecule consisting of many similar or identical monomers linked together.

potential energy

stored energy

prokaryote

A unicellular organism that lacks a nucleus and membrane bound organelles

protein

A three dimensional polymer made of monomers of amino acids.

Proteolysis

decomposition of proteins

ribosome

Makes proteins

RNA

ribonucleic acid

Rough ER

That portion of the endoplasmic reticulum studded with ribosomes.

saturated fat

A lipid made from fatty acids that have no double bonds between carbon atoms

selectively permeable

a property of cell membranes that allows some substances to pass through, while others cannot

smooth ER

That portion of the endoplasmic reticulum that is free of ribosomes.

steroid

lipid molecule with four fused carbon rings

steroid

lipid molecule with four fused carbon rings

stomata

Small openings on the underside of a leaf through which oxygen and carbon dioxide can move

stroma

fluid portion of the chloroplast; outside of the thylakoids

substrate

reactant of an enzyme-catalyzed reaction

Theory of Endosymbiosis

This theory states that cell organelles, like mitochondria, were once tiny, free-living prokaryotic organisms that took up permanent residence inside larger prokaryotic organisms.

Thermodynamics

The study of energy transformations that occur in a collection of matter.

Thylakoid

A flattened membrane sac inside the chloroplast, used to convert light energy into chemical energy.

thylakoid membrane

The photosynthetic membrane within a chloroplast that contains light gathering pigment molecules and electron transport chains.