Honors Biology Midterm Exam Study Guide

Scientific Method

include a series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions.

independent variable

The experimental factor that is changed; is the variable whose effect is being studied.

dependent variable

The measurable effect, outcome, or response in which the research is interested.

Calculating total magnification

take ocular lens power (10x) times the objective lens power ex: 10 × hp (40)= 400

organelles in plant cells

• Cell wall

• Chloroplasts

• Central Vacuole

organelles in animal cells

• Nuclear envelope

• Nucleolus

• Vacuole

• Lysosome

• Centrosomes

Plant cells lack

centrioles and lysosomes

Animal cells lack

cell wall and chloroplasts

Diffusion

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

Osmosis

Diffusion of water through a selectively permeable membrane

active transport

the movement of materials through a cell membrane using energy

cell membrane

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

Parts of the cell membrane

phospholipids, cholesterol, proteins, carbohydrates

Davson-Danielli model

model of the cell membrane in which the phospholipid bi-layer is between two layers of protein.

fluid mosaic model

model that describes the arrangement and movement of the molecules that make up a cell membrane

Adhesion

an attraction between molecules of different substances

Cohesion

the attraction between molecules of the same substance

capillary action

the attraction of the surface of a liquid to the surface of a solid

Density

mass/volume

What makes water polar?

there is an uneven distribution of electrons between the oxygen and hydrogen atoms

Macromolecules

a very large organic molecule composed of many smaller molecules

Carbohydrates

broken down to glucose to provide energy

Lipids

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

Proteins

nutrients the body uses to build and maintain its cells and tissues

Monomers

small molecules that join together to form more complex molecule

Polymers

large compound formed from combinations of many monomers

dehydration synthesis

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

Hydrolysis

breaking down complex molecules by the chemical addition of water

enzymes

proteins that speed up chemical reactions

Substrate

the reactant on which an enzyme works

active sites

the site on an enzyme that attaches to a substrate

systems that effect enzyme function are....

temperature, pH, and the concentration of substrate and enzyme

Prokaryotes vs. Eukaryotes

• Prokaryotes have no nucleus or membrane bound organelles

• Eukaryotes have a nucleus and membrane bound organelles

• Both can reproduce and respond to the environment

Benedict's Test

a biochemical test for the presence of sugars

Iodine Test

chemical test for the presence of starch using a potassium iodide solution. A color change to purple/black indicates a positive result.

Buiret test

tests for proteins

Sudan Red Test (paper bag test)

tests for lipids

Hypertonic

having a higher concentration of solute than another solution

Hypotonic

having a lower concentration of solute than another solution

isotonic solution

a solution in which the concentration of solutes is essentially equal to that of the cell which resides in the solution