Exam #1 Flashcards
How is a covalent bond different from an ionic bond?
Electrons are shared in a covalent bond, electrons are completely given up in an ionic bond, and oppositely charged ions are attracted to eachother
What is the difference between a polar and a non-polar bond?
In a polar bond, electrons are shared UNEQUALLY, so even though the molecule itself is neutral, there is still a positive and a negative side.
In a non-polar bond, electrons are shared EQUALLY, so there is no charge difference across the molecule.
Explain why only polar molecules can form hydrogen bonds.
Polar molecules have a charge difference, so the positive of the one side can be attracted to the negative of a different polar bond.
Non-polar bonds have no difference in charge.
How is an ionic bond different from a hydrogen bond?
Ionic bonds completely give up electrons and oppositely charged ions are attracted to each other.
In a hydrogen bond, electrons are shared covalently (polar), then 2 polar covalent molecules attract to other’s opposite charges.
What is the difference between an organic and inorganic molecule?
Organic contain Carbon and Hydrogen, Inorganic may only contain one OR the other, or neither.
What is a buffer?
A substance that is able to resist a change in pH.
List the general order (weakest to strongest) of the following bonds: \_\_Single Covalent \_\_Hydrogen \_\_Triple Covalent \_\_Ionic \_\_Double Covalent
3---Single 1---H Bond 5---Triple 2---Ionic 4---Double
What are the 4 organic macromolecules?
Carbs, Lipids, Proteins, Nucleic Acids
What are the 4 functions of Carbohydrates?
- Short-term Energy storage
- Long-term Energy Storage
- Structure
- Communication
What are the 3 functions of Lipids?
- Energy storage
- Membrane Structure
- Cell Communication
What are the 8 functions of Proteins?
- Structure
- Movement
- Transport
- Chemical messenger
- Receptors
- Storage (amino acids)
- Defensive
- Enzymes
What are the 2 functions of Nucleic Acids?
- Gene Expression
2. Heredity
Carbohydrate:
Structure:______
Bond:_________
Reaction w/ h20:_____
S: CHO
B: Polar covalent (or H bond)
h20: hydrophilic (water-soluble)
Lipids
Structure:______
Bond:_________
Reaction w/ h20:_____
S:CH
B: Non-Polar Covalent
h20: hydrophobic
Proteins
Structure:______
Bond:_________
Reaction w/ h20:_____
S: Amino Acids
B: primary - hydrogen
secondary- covalent
tertiary- All
quaternary- All
h20: eitherNucleic Acids
Structure:______
Bond:_________
Reaction w/ h20:_____
S: Nucleotides - phosphate, sugar, Nitrogen base
B: Covalent and Hydrogen
h20: Depends
What is an Independent Variable?
The conditions or factors you set up or manipulate ahead of time.
What is a Dependent Variable?
The conditions or factors you are measuring.
What is the 7 steps to the Scientific Method?
- Make observations
- form a hypothesis
- design an experiment
- collect data
- analyze, interpret, and draw conclusion
- determine if hypothesis is supported
- re-evaluate hypothesis, if needed
What is a controlled variable?
Variables that are kept constant throughout the entire experiment.
What is a control group?
An experimental unit that does not get manipulated.
What is an ion?
An atom that has lost an electron.
How many electrons do the first three shells hold?
2, 8, 8
What is an atomic number?
Another name for how many protons and electrons an atom has.
In a water molecule what would be the element with the slightly negative charge?
H20
Hydrogen
What is the specific bond between 2 hydrogen atoms?
Single Non-polar covalent bond
Where do hydrogen bonds form between nucleotides in DNA?
Nitrogen bases
What is composed of amino acids?
Proteins
What is the structure where non-adjacent amino acids are held together with ionic bonds?
Tertiary bonds
What is composed (usually) of just Carbons and Hydrogen?
Lipids
Which word should you NOT use to support a hypothesis?
“Prove”
Define Evolution:
The change in genetic composition over time
Who created the idea of “Natural Selection” ?
Charles Darwin
What is Natural Selection?
a mechanism in which evolution occurs.
Strong live, Weak die off
Define Species:
a population whose members interbreed and can produce viable offspring
What is a Fossil Record?
the appearance of various forms of life in the record mirrors evolutionary relatedness
Prokaryotes —–>
–> Eukaryotes
Unicellular —->
–> Multicellular
Prezygotic barriers [ What prevented mating throughout evolution?]
Temporal - Timing Habitat - Same area? Behavioral - Not attracted to one another Mechanical - Parts don't fit Gametic - Sperm and Egg don't match
Postzygotic barriers:
The offspring do not survive or are infertile
