Unit 1 M.U.B study guide

What is meant by the scientific method?

A systematic method of answering questions

What is a hypothesis?

Cause and effect statement that tries to answer a question

A hypothesis MUST be testible

Controlled experiment

A procedure that tests a hypothesis by collecting information under controlled conditions

Control

The group in an experiment who receives no treatment or the usual treatment

Independent variable

The condition whose values are changed by the experiments

Dependent variable

What is measured or observed

Scientific theory

An explanation of something in the natural world that is supported by a huge amount of data

Inference

A conclusion based on evidence and reasoning

Quantitative vs. Qualitative data

Quantitative data is numbers-based, countable, or measurable. Qualitative data is interpretation-based, descriptive

Biology is the study of…

Living things (life)

Viruses are…

not considered living

Polars

Molecules that have a positive end and a negative end (+ / -)

Hydrogen ends and oxygen ends are…

Hydrogen: positive

Oxygen: Negative

Special properties in water are due to…

Hydrogen bonds

Cohesion and adhesion

Cohesion: Water sticks to water

Adhesion: water sticks to other surfaces

Solutes and Solvents

Solutes: What is being dissolved

Solvent: What the solute is being dissolved IN

The ___________ of water helps organisms maintain __________ by preventing high temperature changes

Heat capacity (specific heat) / homeostasis

pH is the measure of the relative concentration of _________ in a solution

H+ and OH-

A neutral solution has a pH of ____ and has ____ concentrations of H+ and OH- ions

7 / equal

If the concentration of H+ is greater than OH-, meaning…

The solution is acidic (0-6.9)

If the concentration of OH- is greater than H+, meaning…

The solution is basic (7.1-14)

A substance that counteracts changes in pH to maintain an optimal pH conditions (homeostasis) within a cell

Buffer

Anabolic

A + B → C (Energy is input)

Catabolic

C → A + B

Long chain molecules are called…

Polymers

Smaller molecular units are called…

monomers

The process of joining monomers

Dehydration synthesis (water is taken out, energy is input)

The process of breaking large polymers into smaller pieces

Hydrolysis (Water is input, energy is released)

Carbohydrates (saccharides)

Structure: Simple sugars like glucose (starch, cellulose, glycogen)

Function: Short term energy storage

Found in: Grains, starchy veggies, anything sweet

Lipids

Structure: Made of fatty acids

Function: Long term energy storage, components of membranes, chemical messengers

Found in: fats, oils, waxes

Nucleic Acids (DNA & RNA)

Structure: Nucleotides

Function: Store and copy genetic code, make more protein in the cells

Nucleotides are made of three parts: Phosphate group, a 5 carbon sugar, and nitrogen base

Proteins

Structure: Polymers made up of long strands of amino acids monomers joined together with peptide bonds (primary, secondary, tertiary, quarternary)

There are 20 kinds, 12 we make and 8 are found in food (amino, carboxyl and R group)

Function: Special proteins called enzymes control the rate of chemical reactions within cells

Found in: muscles, hair, fur

Enzyme

Type of protein molecule. Function depends on shape. It’s very specific, meaning it will only bond with one type of substrate and only speed up one type of reaction.

Catalyst

Speeds reactions without being used up, lowers activation energy

What causes denaturation?

High temperature, changes in pH or salinity

How does denaturation affect the protein’s shape?

Breaks it down, no longer fitting the substrate

Enzymes are…

NOT used up in a reaction and CAN be used again