#1 Scientific Method

• Steps that scientists use to gather information and answer questions.

• Problem/Question, Hypothesis, Experiment, Conclusion, Theory

• Data-quantitative (numbers) or qualitative (descriptions)

#2 Hypothesis

• Explanation for a question or a problem that can be formally tested.

• Sometimes an “If…then” statement.• Educated guess.

#3 Bias

• Personal and unscientific judgment that may alter the results of an experiment.

• Opinion or belief

#4 Independent Variable

• In an experiment, the condition that is changed because it affects the outcome of the experiment.

• Manipulated variable.

#5 Dependent Variable

• In an experiment, the condition that results from changes in the independent variable.

• Measured variable.

#6 Metric System

• Mass- gram-triple beam balance• Length- meter- meter stick• Volume- liter- graduated cylinder

#7 Heterotroph

• An organism that must consume its food. It cannot produce its own.

• Consumer.• Herbivore, carnivore or omnivore.

#8 Autotroph

• An organism that can produce its own food.

• Uses photosynthesis or chemosynthesis.• Producer.

#9 Biology

• Study of living things.• Animals, plants, bacteria

#10 Biotic

• Living part of an ecosystem.• Ex. Plants, animals, fungi, bacteria

#11 Abiotic

• Nonliving part of an ecosystem.• Air, water, soil

#12 Homeostasis

• Maintaining a stable internal environment.• Including body temperature and amount of

water and nutrients.

#13 Metabolism

• All of the chemical reactions that take place in an organism.

#14 Characteristics of living things

• Made of cells• Reproduce• Have DNA• Grow/Develop• Obtain and use energy• Respond to environment (Homeostasis)• Adapt

#15 Atoms

• Made of protons (+), neutrons(0), and electrons (-).

• Protons and neutrons in nucleus, electrons are in electron cloud.

• Can form bonds to make molecules and compounds.

#16 Bonds

• Covalent Bonds- share valence electrons• Ionic bonds- formed by oppositely

charged ions; + & -• Hydrogen bonds- weak covalent bonds

between hydrogen atoms; found in water and DNA

#16 Ions

• An atom that has a positive or negative charge

• When atoms lose electrons they form a positive ion

• When atoms gain electrons they form a negative ion

#17 Adhesion

• An attraction between molecules of different substances.

• Helps water stick to surfaces.• Capillary action is when water moves

against the force of gravity. Like from the roots to the top of a tree.

#18 Cohesion

• An attraction between molecules of the same substance.

• Helps water stick to itself.• This is why water beads on a smooth

surface.

#19 Acid

• A compound that forms H+ ions in water.• Below 7 on the pH scale.

#20 Base

• A compound that produces OH- ions in water.

• Above 7 on the pH scale.

#21 Carbohydrate

• Contains carbon, hydrogen and oxygen.• Main source of energy from food.• Sugars and starches

#22 Protein

• Contains carbon, hydrogen, oxygen and nitrogen (sometimes sulfur).

• Made of amino acids.• Used for structure, organic catalysts and

gene expression.

#23 Enzyme

• A protein.• Biological catalyst- speeds up chemical

reactions in the body.

#24 Nucleic Acid

• Store and transmit genetic information.• DNA and RNA• Made of nucleotides.

#25 Lipid

• Used for long-term energy storage, protective coatings and insulation.

• Made of a glycerol and three fatty acids.• Fats, oils and waxes.

#26 Monomer

• Subunit or building block of a larger molecule.

• Many monomers bonded together make a polymer.

• Polymers are large molecules.

#27 Monosaccharide

• Monomer of carbohydrates.• Simple sugar.• Glucose, fructose, galactose

#28 Amino acid

• Monomer of proteins.• 20 different kinds• The order of amino acids that goes in a

protein are encoded in DNA.• Has an amino group (-NH2) and a

carboxyl group (-COOH).

#29 Nucleotide

• Monomer of nucleic acids.• Made of a phosphate group, 5-carbon

sugar, and a nitrogen base.

# 30 Cell Theory

• All living things are made of cells• The cell is the basic unit of life• All cells come from preexisting cells

#31 Prokaryote

• Cells that do not contain a nucleus or membrane-bound organelles.

• DNA floats in cytoplasm.• May contain a cell wall.• Ex. Bacteria

#32 Eukaryote

• Cells that contain a nucleus and membrane-bound organelles.

• Animal and plant cells.

#33 Cell Membrane

• Outer boundary of the cell, which regulates what enters and exits the cell.

• Selectively permeable.• Made of phospholipids and proteins.• “Fluid Mosaic”

#34 Ribosome

• Site of protein synthesis (translation).• Spherical body found floating in the

cytoplasm or attached to endoplasmic reticulum.

• Made of rRNA and proteins.

#35 Cytoplasm/Cytosol

• Fluid matrix inside the cell• Many chemical reactions take place here.• Organelles float in the cytoplasm.• Made mostly of water

#36 Nucleus

• Controls the activities of the cell• Contains the hereditary information of the

cell (DNA)• Surrounded by the nuclear envelope• Contains the nucleolus which makes

ribosomes

#37 Endoplasmic Reticulum

• Set of tubular passageways involved with the transport of molecules in the cell.

• Smooth ER- no ribosomes; transports lipids

• Rough ER- ribosomes attached; transports proteins

#38 Mitochondria• The organelle that

releases energy from stored food molecules.

• Site of cellular respiration.

• Highly folded membranes to increase surface area.

#39 Golgi Apparatus

• Stack of flattened membranes that processes and packages proteins to be secreted out of the cell

#40 Chloroplast

• Site of photosynthesis in the plant cell.• Houses chlorophyll.• Made of stacks of thylakoids called grana

and inner space called stroma.

#41 Lysosome

• Small organelles filled with enzymes• Breaks down particles for the cell to use

#42 Cytoskeleton

• Network of protein filaments that help the cell maintain its shape

• Made of microtubules (hollow) and microfilaments (rods)

#43 Vacuole

• Saclike structures used by the cell to store water, salts, proteins, and carbohydrates

• Large central vacuole in the plant cells• Small or not present in animal cells

#44 Centriole

• Only in animal cells• Involved in cell division• Make the spindle that pulls chromosomes

apart

#45 Cilia & Flagella

• Used in cell movement• Cilia- hairlike projection, numerous• Flagella- taillike structures, 1-3

#46 Vesicle

• Transport containers for the cell.• Made from the Golgi Apparatus and the

cell membrane.

#47 Passive Transport

• Movement of particles across cell membranes by moving with the concentration gradient.

• Diffusion or osmosis.• Uses no energy.

#48 Diffusion

• Net, random movement of particles from an area of higher concentration to an area of lower concentration.

• Eventually results in even distribution.

#49 Osmosis

• Diffusion of water across a selectively permeable membrane.

• Depends on the concentration of solutes on either side of the membrane.

#50 Osmotic Solutions• Hypotonic solutions- Solutions that have a

lower concentration of solute than the solution inside the cell. This causes water to move into the cell and the cell will swell.

• Hypertonic solutions- Solutions that have a higher concentration of solute than the solution inside the cell. This causes water to move out of the cell and the cell will shrink.

• Isotonic solutions- The solutions inside and outside the cell have the same concentration of solute. The cell does not change shape.

#51 Active Transport

• Process by which cells transport materials across the cell membrane against a concentration gradient.

• Uses energy.

#52 Endocytosis

• Process of taking material into the cell by means of vesicles.

• Pinocytosis- “cell drinking”• Phagocytosis- “cell eating”

#53 Exocytosis

• The removal of large particles from the cell.

• Vesicles fuse with the cell membrane and force contents out of the cell.

#54 ATP

• Adenosine triphosphate

• Stored cellular energy

• Made from adding a phosphate to ADP.

#55 Photosynthesis

• Process by which plants use light energy to convert water and carbon dioxide into glucose and oxygen.

• Happens in the chloroplast.

6CO2 + 6H2O + light C6H12O6 + 6O2

Carbon+water+sunlightGlucose+oxygenDioxide

#56 Cellular Respiration

• Breaking down of glucose into usable energy (ATP).

• Aerobic• Happens in mitochondria.

C6H12O6 + 6O2 6H2O + 6CO2 + 36 ATPGlucose +Oxygen Water + Carbon + Energy

dioxide

#57 Aerobic

• Reaction that requires oxygen.• Cellular respiration

#58 Anaerobic

• Reaction that does not require oxygen.• Fermentation

#59 Fermentation

• Anaerobic breakdown of organic substances.

• Alcoholic- gives of alcohol & carbon dioxide

• Lactic acid- gives off lactic acid.

#60 Cell Cycle

M phase

A.G1

B.S

C.G2

D.Metaphase

#61 Chromosome

• Compact form of DNA and protein in the nucleus of a cell about to divide.

• Come in homologous pairs in diploid cells.

Centromere

Sister Chromatids

#62 Chromatin

• Genetic material that is found in the nucleus of a nondividing cell.

• Unwound, stringy form of DNA.

#63 Mitosis

• Cell division in which two daughter cells are produced, each containing a complete set of chromosomes.

• Done by somatic cells.• Diploid cell division.• Prophase, metaphase, anaphase,

telophase.

#64 Cytokinesis

• Division of the cytoplasm.• Happens at the end of cell division.• Animal cells- pinch inwards; cleavage• Plant cells- form cell plate down center of

cell

#65 Gamete

• Sex cells• Female- egg cell; Male- sperm• Haploid• Made during meiosis

#66 Haploid

• Cell with one of each type of chromosome.• n• Sex cells

#67 Diploid

• Cell with two of each type of chromosome.• 2n• Somatic cells.

#68 Meiosis

• Type of cell division in which a body cell produces four sex cells (gametes).

• Each gamete contains half the number of chromosomes as the original cell.

• All four cells produced are genetically different.

#69 Crossing Over

• When chromosomes pair up and exchange parts of their chromatids.

• This creates genetic variations.• Happens during prophase I.