Biology Exam 1

Hypothesis

Specific question/statement that ideally has a yes/no answer with only one alternative

Experiment

Limit variables as much as possible

Most researched groups

White males age ranging from 18-25

Phen Fen incident

Diet drug for obesity was effective but not evaluated thoroughly and damaged people’s hearts

Conclusions

2 possible outcomes: did or did not support hypothesis

Replicate

Re-do experiment to thoroughly evaluate the hypothesis and results

Publication

Share knowledge/findings with people

Scientific method steps

1. Research

2. Hypothesis

3. Experiment

4. Results

5. Conclusion

6. Replicate

7. Publish

All living things are made of

Cells

Unicellular

Organism has only one cell

Multicellular

Organism has multiple cells

Hierarchal organization

1. Organelles

2. Cells

3. Tissues

4. Organs

5. Systems

6. Organism

7. Population

8. Community

9. Ecosystem

10. Biome

11. Biosphere

Asexual reproduction

One organism reproduces

Lack of diversity, hard for population to survive

Sexual reproduction

2 organisms reproduce

Diverse, multiple genetics

Living things

Grow and develop

When does existence start?

Conception

Living things obtain and use

Energy

Phototroph

Uses light as energy source

Chemotroph

Uses chemicals as energy source

Autotroph

Gets carbon from atmosphere

Heterotroph

Eats carbon

Living things respond to

Environment

Homeostasis

Body constantly trying to have optimum conditions (a balance)

Atom

Basic unit of matter, smallest particle that maintains all of the properties of that matter

Nucleus

Center contains protons (+) and neutrons (-)

Energy levels

Electrons (-) orbit nucleus

Atomic number

Number of protons

Atomic mass

Number of protons and neutrons

Atomic mass - atomic number =

Neutrons

The number of protons =

Number of electrons

Elements

Made up of one type of atom

Compound

Made up of more than one type of atom

Isotopes

Same number of protons but different number of neutrons

Can be dangerous, some are radioactive

When something is radioactive, the nuclei is

Unstable

How do atoms achieve stability?

Gain and lose electrons

How many electrons does an atom need to be stable?

8 electrons

Whenever a bond is made or broken, what happens?

Chemical change occurs

Ionic

Gains/loses electrons

Ex. NaCl

Covalent

Shares electrons

Ex: water

Reactions can go in direction based on the flow of

Energy

How does energy flow?

High to low

Biological molecules

1. Water

2. Carbohydrates

3. Lipids

4. Proteins

5. Nucleic acids

Water is liquid at average

Earth temperature

What is the average global temperature?

Approximately 75 degrees

What does water do when it solidifies?

Expand

What kind of molecule is water?

Polar molecule

Polar molecules

Strong attraction for other charged molecules (sticky)

Accreation

How the world was made

Acids

Increase the concentration of H+ ions when they dissociate in water

Ex: HCl - H+ + Cl -

Bases

Increase the concentration of OH- ions when they dissociate in water

Why is water considered neutral?

It splits into equal amount of both ions

The PH scale goes from numbers

0 - 14

What set of numbers are acids on the PH scale?

0 - 6

What set of numbers are bases on the PH scale?

8 - 14

What number is considered neutral on the PH scale?

7

On the PH scale, acids go from

High to low

ex: 1 is stronger than 4

On the PH scale, bases go from

Low to high

ex: 12 is stronger than 9

On the PH scale, the acids/bases increase by

Factors of 10

On the PH scale, how much stronger is 2 compared to 5?

10000x stronger

What are the most common elements in living things?

Carbon, hydrogen, oxygen, and nitrogen

Inorganic compounds do not contain

Carbon bound to hydrogen

Carbon has the ability to

Form single, double, or triple bonds with itself and other molecules

Polymerization

Small units (monomers) joining together to form polymers

Dehydration synthesis

Takes water out while building polymers

Dehydration hydrolysis

Water is added to break a large molecule into smaller molecules

Hydrocarbons

Made up of hydrogen and carbon

Carbohydrates

Sugars and starches that consist of C, O, and H

Ratio: C:H:O - 1:2:1

Monosaccharides

Single sugar

Glucose

Product of photosynthesis

Galactose

Part of the principle sugar in milk

Fructose

Found in fruit

Sugar formula

C6H12O6

The varying atom arrangements make them different

Disaccharide

Double sugar

2 monosaccharides bond by

Removing one H and one OH to form water

Sucrose is made up of

Glucose and fructose

Lactose is made up of

Glucose and galactose

Maltose

Glucose and glucose

Polysaccharides

Hundreds of monosaccharides joined together and are used to store excess sugar

Cellulose

Used to give strength to plant cells

Carbs provide energy for

The cell

How is energy released?

Bonds within the molecule are broken

Proteins

Contain N,H,O and are made up of amino acids joined together by dehydration synthesis

What are amino acids?

Organic chains that have amine and carboxyl groups

What does a complete protein consist of?

One or more polypeptide chains and several functional groups

What is the function of proteins?

To carry out chemical reactions, pump material, and regulate movement

Altering the shape alters the protein’s ability function

What is the lock and key mechanism?

When an enzyme (protein) has an active site and a substrate fits into the site (key in the lock) to make products

Primary level of organization

Order of amino acids

Secondary level of organization

Localized bending and coiling caused by hydrogen bonding

Tertiary level of organization

Bending/folding of the entire polypeptide chain caused by disulfide bridges

Enzymes are

Biological catalysts

Catalyst

Regulates chemical reactions without being used in reaction

Substrates

What is acted upon

Active site

Where reaction occurs

Nucleic acids are

Composed of nucleotides

3 parts to a nucleotide

1. Five C sugar

2. Phosphate group

3. Nitrogenous base

DNA

Contains genetic material

What is DNA’s sugar?

Deoxyribose sugar

DNA’s structure is a

Double helix

DNA contains

Thymine

DNA does not contain

Uracil