Biology Exit Exam

Theory

A hypothesis that has been tested with a significant amount of data, backed by strong evidence

Law

A descriptive statement or equation that reliably predicts events under certain conditions

Hypothesis

A testable prediction, often implied by a theory

Control

In an experiment, the standard that is used for comparison

Experimental group

In an experiment, the group that is exposed to the treatment, that is, to one version of the independent variable.

Independent variable

The experimental factor that is manipulated; the variable whose effect is being measured. Plotted on the x axis

Dependent variable

The outcome factor; the variable that may change in response to manipulations of the independent variable. Plotted on the y axis

Autotrophs

Organisms that are able to make their own food

Heterotrophs

An organism that obtains organic food molecules by eating other organisms or their by-products.

Diffusion

Movement of molecules from an area of higher concentration to an area of lower concentration; requires no energy

Osmosis

Diffusion of water through a selectively permeable membrane; moves from higher to lower water concentration

Active transport

Energy-requiring process that moves material across a cell membrane against a concentration difference

Botany

The scientific study of plants

Biology

The scientific study of life

Chemistry

The study of the properties of matter and how matter changes

Genetics

The scientific study of heredity

Ecology

Scientific study of interactions among organisms and between organisms and their environment

Evolutionary Biology

The study of organisms and their changes

Molecular Cell Biology

The study of the molecules and the structures that make up the cell, the reactions that occur within the cell, including DNA.

Stomata

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

Guard cells

The two cells that flank the stomatal pore and regulate the opening and closing of the pore.

Respiration

Biochemical process in which an organism gets energy by breaking bonds of ATP

Aerobic respiration

The process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.

Anaerobic respiration

Respiration in the absence of oxygen. This produces lactic acid.

Photosynthesis

Plants use the sun's energy to convert water and carbon dioxide into sugars

Stimulus

A change in an organism's surroundings that causes the organism to react

Neuron

A nerve cell; the basic building block of the nervous system

Impulse

An electrical message that carries information in the nervous system.

Hormone

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

Receptor molecules

Proteins on surface of cell membrane that receive signals from the nervous and endocrine system

Organic compound

Any compound of carbon and another element or a radical

Sugars

Carbohydrates found both in food and in the body

Fatty acids

Chains of carbon atoms bonded to hydrogen atoms; building blocks of lipids

Amino acids

A simple organic compound containing both a carboxyl (—COOH) and an amino (—NH2) group.

Nucleotides

Basic units of DNA molecule, composed of a sugar, a phosphate, and one of 4 DNA bases

Covalent bond

A chemical bond that involves sharing a pair of electrons between atoms in a molecule

Ionic bond

Formed when one or more electrons are transferred from one atom to another

Dehydration synthesis (condensation)

A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.

Hydrolysis

Breaking of covalent bonds

Hydrogen bonds

Very weak bonds; occurs when a hydrogen atom in one molecule is attracted to the electrostatic atom in another molecule; strongest IMF

London Dispersion forces

The intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles; weakest IMF

Dipole-dipole forces

Attractions between oppositely charged regions of polar molecules

Ion-dipole forces

Attractive forces between an ion and a polar molecule

Starch

Energy store in plants (polysaccharide)

Glycogen

Energy store in animals (polysaccharide)

Carbohydrates

The starches and sugars present in foods; simplified sugars that supply energy

Lipids

Substances that are soluble in nonpolar solvent

Protein

A three dimensional polymer made of monomers of amino acids.

pH

Quantitative measure of the acidity or basicity of aqueous or other liquid solutions where 1 is high acidity and 14 is high basicity

Cells

The basic unit of structure and function in all living things

Enzymes

Catalysts for chemical reactions in living things

Catalysts

Chemical agents that selectively speed up chemical reactions without being consumed by the reaction.

Product

A substance produced in a chemical reaction

Reactant

A chemical substance that is present at the start of a chemical reaction

Reaction time

The time elapsing between the beginning of the application of a stimulus and the beginning of an organism's reaction to it.

Animal cell

A small living part of a multicellular organism that eats to gain energy and reproduces sexually; Lacks a cell wall and chloroplast

Plant cell

A small living part of a multicellular organism that makes its own food in chloroplast and reproduces sexually or asexually; contains cell wall, chloroplast, and large vacuole

Mitochondria

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

Golgi apparatus

A system of membranes that modifies and packages proteins for export by the cell

Rough Endoplasmic Reticulum (RER)

System of internal membranes within the cytoplasm. Membranes are rough due to the presence of ribosomes. functions in transport of substances such as proteins within the cytoplasm

Smooth Endoplasmic Reticulum (SER)

The region of the endoplasmic reticulum that has few or no ribosomes on its cytoplasmic surface and synthesizes carbohydrates, lipids, and steroid hormones; detoxifies chemicals like pesticides, preservatives, medications, and environmental pollutants, and stores calcium ions

Vacuole

Cell organelle that stores materials such as water, salts, proteins, and carbohydrates

Ribosomes

Site of protein synthesis

Chloroplast

Capture energy from sunlight and use it to produce food for the cell

Thylakoid

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

Stroma

The fluid of the chloroplast surrounding the thylakoid membrane; involved in the synthesis of organic molecules from carbon dioxide and water.

Cytoplasm

A jellylike fluid inside the cell in which the organelles are suspended

Cytosol

The semifluid portion of the cytoplasm.

Centrosome

A structure in animal cells containing centrioles from which the spindle fibers develop.

Nucleus

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

Nucleolus

Found inside the nucleus and produces ribosomes

Lysosome

An organelle containing digestive enzymes

Nuclear envelope

A double membrane that surrounds the nucleus in the cell

Cell wall

A rigid layer of nonliving material that surrounds the cells of plants and some other organisms.

Cell membrane

A cell structure that controls which substances can enter or leave the cell.

Peroxisome

A microbody containing enzymes that transfer hydrogen from various substrates to oxygen, producing and then degrading hydrogen peroxide.

Kingdoms

Archaebacteria, Eubacteria, Protista, Fungi, Plantae, Animalia

Domains

Bacteria, Archaea, Eukarya

Species

A group of similar organisms that can breed and produce fertile offspring

Tissues

Groups of cells that are similar in structure and function

Specialization

The adaptation of an organism or organ to a special function or environment

Red blood cells

Blood cells that carry oxygen from the lungs to the body cells.

White blood cells

Blood cells that perform the function of destroying disease-causing microorganisms

Basophils

A circulating leukocyte that produces histamine.

Eosinophils

A white blood cell containing granules that are readily stained by eosin.

Leukocytes

White blood cells, fight infection

Plasma

Liquid part of blood; transports everything EXCEPT oxygen

Platelets

Small colourless, disk-shaped cell fragment with no nucleus that clots blood

Skeletal system

Protects and supports body organs and provides a framework the muscles use to support movement. Made up of bones and joints

Muscular system

Allows manipulation of the environment, locomotion, and facial expression. Maintains posture, and produces heat.

Circulatory system

Transports oxygen, waste, nutrients, hormones, heat, etc… around the body

Nervous system

The body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

Digestive system

Breaks down food into absorbable units that enter the blood for distribution to body cells.

Excretory system

The system that removes waste from your body and controls water balance

Lymphatic system

Composed of a network of vessels, ducts, nodes, and organs. Provides defense against infection.

Integumentary system

Consists of the skin, mucous membranes, hair, and nail

Endocrine system

The body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream

Urinary system

kidneys, ureters, urinary bladder, urethra; elimintes nitrogenous wastes

Reproductive system

Reproduce offspring- produce male sex cells (sperm) and female sex cells (oocytes)

Cardiovascular system

Blood vessels transport blood, which carries oxygen, carbon dioxide, nutrients, wastes, etc. The heart pumps blood.