Biology Unit Exam Review

Scientific Method

Steps of Sci Method:

ProblemHypothesisTesting Hypothesis (procedure)Record Data (# or details)Analyze and Form ConclusionsReplicate Work

Variables

Controlled Experiment: Two groups differ by one factor;

control is present

Control vs Experimental Group: Experimental group has something changed (i.e. amount of light, etc)

Variables

Independent Variables:Changed by scientist to see

what happens

Dependent Variable: Changes in response to the change the scientist makes to the independent variable.

Seven characteristics of living things

Respond to stimuli Uses energy- metabolism Maintains homeostasis Made up of one or more cells Reproduces, contains hereditary

information Growth and development Evolves

Chemistry

Covalent Bonds

Bond formed by sharing electrons

Ionic Bond

Bond that forms by transferring the electrons; can create an electrical attraction

Elements, Compound, Mixture

Elements: substance made up of one kind of atom (i.e. oxygen)

Compound: made up of two or more elements (i.e. water)

Mixture: substances that are mixed without forming a new chemical bond (i.e. saltwater)

2H2O + O2---2H2O2

Atoms= hydrogen, oxygenReactants: 2H2O + O2

Products: 2H2O2

Atoms: 8 Hydrogen, 8 Oxygen

pH Scale

pH runs from 1-147 is neutralBelow 7 acidic (with 1 being more acidic)

Above 7 basic with 14 being most basic

pH Scale

The pH scale measures the amount of hydrogen ions in a solution. pH stands for powers of hydrogen.

Neutralization Reaction

Reaction that occurs when acids and bases are combined to form water and salt

EX: NaOH + HCl----NaCl + H2O

Solution & Its Parts

Substances are spread evenly throughout the mixture

EX: Air- comprised of N, O, CO2

Two parts:

a. Solvent: substance that a solute is dissolved in

b. Solutes: substance that is dissolved in a solvent

Biochemistry

Organic Compounds

Compounds that contain carbon and occur naturally only in the bodies and products of an organism

Monomers

Carbs: sugar Proteins: amino acids Nucleic Acid: nucleotide

Parts of a lipid

3 fatty acids and glycerol

Classify:

A. carb B. carb C. Lipids D. Lipids E. Lipids F. Nucleic Acids G. Nucleic Acids H. Proteins I-K. Carb

Disaccaharide: 2 sugars (maltose)

Polypeptide: 2+ amino acids

connected by peptide bonds

Polar vs. Nonpolar

Water is polarPolar molecule: a molecule that has a partial positive and partial negative charge

Only polar substances will dissolve in water; non polar will not.

Enzymes

13. Proteins that are necessary for life

14. It is a catalyst, which causes a reaction to occur

15.pH, temperature affect enzymes

17. Area where substrate binds

Cell Theory

1. All living things are composed of one or more cells

2. Cells are organisms’ basic units of structure and function

3. Cells come only from existing cells

Prokaryotic vs. Eukaryotic Cells

Prokaryotes: Lack any internal membrane bound structures (most organelles) and nucleus

Ex: bacteriaEukaryotes: have nucleus; plants & animals

Fluid Mosaic Model

Fluid because: the phospholipid and protein

molecules are able to move around not stuck in one place and

Mosaic because: The membrane contains a variety of

proteins embedded within the phospholipid.

Phospholipid Bilayer

Permeable

Permeable membrane – allows everything to pass through

(selectively)Semi-permeable – only allows some things to pass through

Impermeable – does not allow anything to pass

OrganizationCells to tissue

Tissue to organsOrgans to organ system

Organ system to organism

Active vs. Passive

Active Energy Required Moves from low

concentration to high concentration

Passive No energy required Moves from high

concentration to low concentration

Diffusion

Movement of molecules from an area of high concentration to an area of lower concentration

Passive Transport

Diffusion

Concentration Gradient

Occurs when there is a difference between high and low concentration

Osmosis

Diffusion of water across a selectively permeable membrane from region of high water concentration to a region of low water concentration

Passive

Plasmolysis vs. Cytolysis

Plasmolysis: shrinking of cytoplasm (result of hypertonic solution)

Cytolysis: cell explodes due to hypotonic solution

Endocytosis

Transporting material into cell by vesicle

EX: Pinocytosis: small liquids are

taken into cell by vesicle Phagocytosis: solid particles

ingested into cell by vesicles

Exocytosis

Transporting material out of cell by vesicle

Type of Solution

Where is there more solute

Where is there more solvent (water)

What direction does water move

What happens to the cell

Hypotonic Inside cell Outside cell Inside Cytolysis (explode)

Hypertonic Outside cell Inside cell Outside Plasmolysis (shrink)

Isotonic Equal Equal Constant Nothin

Photosynthesis & Cellular Respiration

IV. Photosynthesis and Cellular Respiration

1. What is photosynthesis?The process of capturing energy of sunlight and transforming it into chemical energy.

a.Where in the cell does it take place?

Chloroplast

b. What are the reactants and products? Write the overall

equation for photosynthesis. The overall chemical reaction involved in

photosynthesis is: 6CO2 + 6H2O (+ light energy) C6H12O6

+ 6O2. In simple terms, we can say it the following

wayCarbon Dioxide + Water (+ sun energy)

Glucose + Oxygen

Reactants:Carbon dioxide, water, energyProducts:Glucose, oxygen

2. What is the difference between autotrophs and

heterotrophs? Autotrophs:

Organisms that make their own food EX: green plants, algae

Heterotrophs: Organisms that cannot make their own

food and must depend on other plants or animals as food source

3. What is aerobic cellular respiration?

Where in the cell does it take place? Aerobic Respiration:

Occurs in presence of oxygenOccurs in the mitochondriaYields about 36 ATP

4. How is aerobic respiration different from anaerobic cellular

respiration?

Anaerobic Respiration:Occurs without oxygenOccurs in the cytoplasmYields 2 ATP

5. What is another name for anaerobic respiration?Fermentation