Exam 1 Flashcards
4 levels of organization (in order)
Atoms
Molecules
Organelles
Cells
What are the important properties of life
- order
- growth and development
- energy processing
- regulation
- response to the environment
- reproduction
Cell represents
Basic unit of life
Scientific method
- Observation
- Hypothesis
- Experiment
- Collect and analyze data
- Accept or reject hypothesis
Hypothesis
Tentative explanation
Theory
Well sustained explanation
Compare and contrast hypothesis and theory
A theory has been tested multiple times and is scientifically acceptable.
Hypothesis must be
Testable and falsifiable
Difference between an element and a compound
A compound is a substance that consists of two or more elements in a fixed ratio. An element is a substance that cannot be broken down
Difference between essential elements and trace elements
Essential elements comprise approx. 99.9% of organisms (maxi- and micro- nutrients) trace are in minute quantities
What are the 6 elements that comprise organic molecules in cells
S, O, C, H, N, P
What are the 5 ions found in cells
Ca, K, Na, Ch, Mg
4 macromolecules
Proteins, carbohydrates, lipids, nucleic acids
3 subatomic particles
Protons, neutrons, electrons
Positively charged?
Protons
Negatively charged?
Electrons
Uncharged
Neutrons
Protons located in
Nucleus
Neutrons located in
Nucleus
Electrons located?
Surrounding the nucleus
Atomic #
Signifies the # of protons
What else doesn’t the atomic # give
of electrons
Why are elements naturally uncharged
of protons and neutrons are qual
Atomic mass
It represent # of protons and neutrons combined
What happens if proton # is changed
Changes atomic # so it changes the element
What happens when the # of neutron changes
Forms an isotope
Isotopes
Variants of an atom with a diff atomic mass
If N-14 and N-15 are isotopes what does that mean?
of neutrons are diff
What happens to an element when electron number is changed
It will bond
Election orbital order
2
8
8
What is the outermost electron orbital called
Valence she’ll
What are the elections called in the outermost orbital called
Valence electrons
What are 2 main reasons that “drive” elements to form bonds
To fill the outer shell or so they can be uncharged
List the five major types of bonds in order
Nonpolar covalent Polar Covalent Ionic bonding Hydrogen bonding Van der waals
What happens during a covalent bond
A molecule forms when two or more atoms share electrons
Difference between no polar and polar covalent
Nonpolar involves equal sharing of eke tons. polar involves unequal
Electro negativity
Refers to an atoms affinity to attract electrons
Rank C H N and O based on electronegativity
O >N>C=H
Be prepared to determine if a covalent bond between 2 elements is polar or no polar
N: s-s O-O N-N C-H
P: O-C and O-H
N-C and N-H
What happens to elements that form polar covalent bonds?
Gain stability; higher electronegativity
Which covalent bond does hydrogen bonding rely on?
Polar covalent
Which covalent bond does van der waals rely on?
No polar covalent
Describe hydrogen bonding
Occurs when an atom with a partial + charge is attracted to an atom w/ a partial - charge
Describe van der waals
Bonds when electrons charge is not evenly distributed. Involved between no polar. It’s very weak.
Describe ionic bonding
Involved the attraction of oppositely charged ions. Ions form when elements gain or loss electrons to achieve a full outer orbital
What are the two types of ions and which is + and -
Cation +
Anion -
How do cations form?
Lose or give away electrons
Why do cations form?
Because there is either 1, 2 or 3 valence electrons
How do anions form?
Steal or gain electrons
Why do anions form?
B/c there is either 5, 6, or 7 valence electrons
Properties of water
Cohesive behavior, ability to mod temp, expansion upon freezing, versatility as a solvent, less dense as a solid than liquid
Is water polar or nonpolar and why?
Polar hydrogen bonding water
What does it mean to say that water is both cohesive and adhesive
It sticks to itself and other surfaces
Why is waters ability to mod temp so important for life?
Evaporative cooling contributes to temp stability
How does the hydrogen bonding of water molecules change with water changes from liquid to solid
Hydrogen bonding becomes more ordered as water solidifies
Solution
A homogenous liquid mixture of two or more substances
Solvent
Dissolving agent
Solute
Dissolved substance
Why is water such a good solvent?
Because it’s good at dissolving substances
Hydrophobic
“Water hating” nonpolar molecules. Doesn’t dissolve in or interact with water
Hydrophilic
“Water loving” polar and charged. Dissolved easily in water; interacts with water
Acid
Releases H+; high H- concentration
Base
Consume H+; low H- concentration
What pH values are acidic
1-6
What pH are alkaline
8-14
What does pH measure)
Acidity
Compare the hydrogen ion concentration of acidic and basic solutions
Hydrogen ion concentration increases as pH decreases, hydrogen ion concentration changes by 10^x where x is the pH value change
Why is carbon used for life
Most versatile atom on earth (can form up to 4 covalent bonds) found in every organic compound; forms basis for all macromolecules; backbones can be linear, branched, or circular
Hydrocarbon
Organic molecule that consist of just C and H
Chemical formula
Gives the type and # of each element
Structural formula
Gives the physical arrangement of each element
Isomer
2 molecules that have the same chemical formula but diff structural formula
3 types of isomers
Simple structural, cis trans, enantiomers
Simple structural isomers
Simple re-arrangement of atoms
What is required to have a cis trans isomer
Differ in spatial arrangement due to inflexibly to double bonds
Cis
The two Xs are on the SAME side
Trans
2 Xs are on the OPPOSITE sides
Enantiomers
Two molecules are considered “mirror images” typically observed with amino acids and “sugars” with diff groups attached to a central carbon
What are enanti omers also called?
Optical isomers
What are the 6 important functional groups
Amino, phosphate, carboxyl, carbonyl, hydroxyl, sulfhydryl
What functional groups contain carbon
Carboxyl and carbonyl
What functional groups contain hydrogen
All
What functional groups contain nitrogen
Amino
What functional groups contain oxygen
Phosphate, carboxyl, carbonyl, hydroxyl
What functional groups contain sulfur
Sulfhydryl
What functional groups contain phosphorus
Phosphate
Compare and contrast the carbonyl and carboxyl groups
Both have double bond with oxygen but carboxyl has 2 oxygens
Compare and contrast carboxyl and hydroxyl.
Hydroxyl doesn’t have carbon
What are the reactants in a chemical reaction
The starting materials
Products
Result of a reaction
What does it mean to say some chemical reactions are reversible
The can be the reactants or product
What are the 4 important biological macromolecules
Carbohydrates, lipids, proteins, and nucleic acids
Monomer
Single common subunit
Polymer
Collection of monomers
What happens during a dehydration reaction
Reactions combine monomers to produce polymers
How is water involved in dehydration reaction
Takes away water, loss of water, water is removed
How is energy involved in a dehydration reaction
It consumes energy
What happens during an hydrolysis reaction
Break down polymers into monomers
How is water involved in a hydrolysis reaction
It used water to break the polymer apart. Water is added
How is energy involved in a hydrolysis reaction
Generates energy
During which chemical reaction is a polymer the product
Dehydration
During which chemical reaction is a polymer the reactant
Hydrolysis
What is the polymer name for the macromolecules
Polysaccharide, protein, nucleic acids
Identify the monomers that correspond to each macromolecule polymer
Monosaccharides, amino acids, nucleotide
Identify the name for the connecting bond in each macromolecule polymer
Glycosidic, peptide, and phosphodiester
Which macromolecules contain a carbonyl
Polysaccharide
Which macromolecules contain a carboxyl
Protein
Which macromolecules contain an amino acid
Protein
Which macromolecules contain a phosphate
Nucleic acid
Which macromolecules contain a hydroxyl
Nucleic acid
What are the 3 types of lipss
Fats, phospholipids, and steroids
What is the composition of fats
Composed of glycerol and either 1, 2, or 3 fatty acids
What is the composition of a fatty acid
Hydrocarbon chain with a carboxyl group
What are the functions of fats?
Energy storage/ source; water repellent, protection, and insulation; lubricantion
What are the water interaction properties of fats
Hydrophobic
Compare and contrast saturated and unsaturated fatty acids
Saturated are straight and linear unsaturated is bent and linked
Which type of fatty acid contains a double covalent bond between carbons
Unsaturated
Which type of fatty acid result in a more solid consistency?
Saturated
Which type of fatty acid result in a more liquid consistency?
Unsaturated
What is the composition of phospholipids
Composed of glycerol, 2 fatty acids and 1 phosphate group
What is the major function of phospholipids
Forms bilayers in the cell membrane
Which part of the phospholipid is hydrophilic
The polar phosphate head that stays on the outside
What part of the phospholipid is hydrophobic
The nonpolar fatty acid tail that’s on the inside
What is the composition of steroids
Group of lipids with 4 interconnected C rings
What are the two types of steroids
Sterols and hormones
What are the water interaction properties of steroids
Hydrophobic and hydrophilic
Compare and contrast fats and phospholipids
Fats have 1, 2, or 3 fatty acids while phospholipids have 2 and have a phosphate group. Both have glycerol
What is the general chemical formula for carbohydrates
CH2O
What is a monosaccharide
Basic unit of carbs it’s the simplest sugar
What is a polysaccharide
Long chains of monosaccharides
What is the name of the specific bond that connects monosaccharides together in a polysaccharide
Glycosidic bond
What is the functional group important in carbohydrates
Carbonyl and hydroxyl
Where is the carbonyl group in Aldose
End
Where is the carbonyl group in ketone
Middle
What are the properties of an alpha glycosidic linkage
More flexible; helical structural; easily broken; storage molecules
What are the properties of a beta glycosidic linkage
More rigid; linear structure; very stable structural molecules
What are the properties of a storage polysaccharide
Starch in plants and glycogen in animals
What are the properties of a structural polysaccharide
Cellulose in plant cell walls; chitin in fungal and Algal cell walls; Peptidoglycan in bacterial cell walls
What is amylose
Unbranched starch in plants
What is Amylopectin
Branched starch in plants
Compare and contrast amylose and amylopectin
Amylose is unbranched and amylopectin is branched
What kind of polysaccharide is starch
Storage in plants
What kind a polysaccharide is glycogen
Storage in animals
What kind a polysaccharide is cellulose
Structural in plant cell walls
What kind of polysaccharide is chitin
Structural and fungal and Algal cell walls
What kind of polysaccharide is Peptidoglycan
Structural in bacterial cell walls
What are the potential functions of proteins
Enzymatic transport protection identification communication
What is the monomer subunit of proteins
Amino acids
How are proteins involved in chemical reactions
The build up of things like enzymes
Why are proteins considered directional
They have a start and an end
What term is used for the start of a protein
N-terminal
Which functional group corresponds to or is located at the “beginning” of a protein
Amino
What term is used for the “end of a protein”
C-terminal
Which functional group corresponds to or is located at the “end” of a protein?
Carboxyl
How many diff amino acids are naturally found in proteins?
20
What are the 4 components of an amino acid?
Central carbon, carboxyl group, amino group, r-group
What does the R group represent?
Variable
What are the 4 levels of protein organization/structure?
Primary, secondary, tertiary, quaternary
What does protein structure represent
Primary: order of the amino acids from beginning to end
What bond/ interaction holds primary structure together?
Peptide covalent bonds
What does secondary structure represent?
Formation of localized folding of the peptide chain
What are the two types of 2nd structure shapes?
Alpha helix and beta sheets
What bonds/ interactions hold secondary structure together
Hydrogen bonding between backbone atoms
What part of the protein chain participates in 2nd structure interactions
Peptide chain
What does the tertiary structure represent
Overall 3D shape of a protein
What bonds/ interactions hold tertiary structure together
Disulfide bonds, ionic bonding, hydrogen bonding, van der waals
Which amino acid group participates in van der waals interactions?
R-group
Rank the tertiary structure bonds/ interactions from strongest to weakest
Disulfide bonds, ionic bonding, hydrogen bonding, van der waals
What part of the protein chain participates in the tertiary interactions
R group
What does quaternary structure represent
Polypeptide interaction
Denaturation
Refers to removal of quaternary tertiary and secondary structure
Re-nature ration
Refers to allowing a protein to refold into its proper shape
What to environmental changes will lead to protein denaturation
PH or temperature
What is the name for proteins that help other proteins fold correctly
Chaperone
What are the two types of nucleic acid
Rna and DNA
What is the monomers of nucleic acid
Nuclear tides
What are the three components to nucleotides
Phosphate groups five carbon sugar and nitrogenous bases
Why are nucleic acid considered directional
They have a start and end in
What term is used for the start of a nucleic acid
Five prime
Which functional group corresponds to or is located at the beginning of a nucleic acid
Phosphate
What term is used for the end of a nucleic acid
3 prime
Which functional group corresponds to or is located at the end of a nucleic acid
Hydroxyl
What is a nucleotide composition of DNA
Adenine thymine guanine cytosine
Compare and contrast the nucleotide composition of DNA and RNA I
DNA has thymine RNA has uracil
Why is a nucleotide composition of RNA
Adenine uracil guanine cytosine
What specific five carbon sugar is found in DNA
Deoxyribose
What specific five carbon sugar is found in RNA
Ribose
What is the main function of DNA
Genetic info storage in cells and some viruses
What are some functions of RNA
Genetics storage info in some viruses also is involved in protein production
What are the structural properties of DNA
Simple secondary structure
Complementary nature of DNA
Base Pairing
What bond is important in base pairing
Hydrogen bonding
How many hydrogen bonds connect AT base pair
2
How many bonds connect to the GC base pair
3
Which nucleotides are considered purines
Ag
Nucleotides are considered pyrimidines
Ct
What the phenomenon did Griffith observed
Transformation
What Is the difference between r strain S strain
S is smooth appearance are had a rough appearance
What happen when the r strain is injected into mice
The mouse lived
What happen when the S strain was injected into the nice
It died
What happens when the heat killed S train was injected into mice
Live mouse
What happen when the heat killed S strain and the living r strain were mixed together before injecting into mice
Mouse died
What did Avery Macleod and McCarty do
They had three experiments with DNA RNA and proteins. In the first they inserted DNase in the second rnase and the third protease no transformation was in the fest so DNA is required for transformation
What did Hershey and Chase do
They worked with bacteria and a bacteriophage
Lifecycle of a virus
Viruses are small acellular micro organisms are composed of nucleic acid contained within a protein coat viruses reproduce by injecting their genetic info into a host cell then the host cell makes new viruses
What is the macromolecule composition of the viruses
Protein
What radioactive element was used to label DNA
Phosphorus
What radioactive element was used to label protein
Sulfur
What instrument was used to separate cells from viruses
Centrifuge
When viruses with radioactive DNA were mixed with bacterial cells then centrifuge where did the radioactivity end up
On the bottom
When viruses with radioactive Protein were mixed with bacterial cells then centrifuge where did the radioactivity end up
Top
What was chargaffs contribution to the discovery of the structure of DNA
He studied the DNA composition of organisms
Where is Franklin and Wilkins contribution to the discovery of the structure of DNA
They use x-rays to photograph
Watson and crick’s contribution to the discovery of structure of DNA
Credited with the scuplting structure of DNA