Unit 1 - Chemistry of Life Flashcards
What do all life on earth have in common?
they are all made of cells, atoms, and elements (carbon, hydrogen, nitrogen, oxygen, phosphorus, + “sulfur”)
Ionic Bonding
a bond in which electrons are transferred from one element to another resulting in charged molecules (ions)
Cations
positively charged - lose electrons
Anions
negatively charged - gain electrons
Covalent Bonding
a bond in which electrons are shared between elements
Electronegativity
an atom with a strong pull on another atoms electrons which results in partial charge
Non Polar Covalent Bonds
equal sharing of electrons (hydrophobic)
Polar Covalent Bonds
unequal sharing of electrons because an electronegative atom will pull on another atoms electrons (H2O) - hydrophillic
We can tell if a molecule is polar because…
O, N, S, P are in the model because they cause the region of the molecule to be polar (hydrophillic) due to the high electronegativity of those elements
We can tell if a molecule is non-polar because…
long chains of carbons, and ringed carbon structures are non-polar (hydrophobic)
Nitrogen means that it is
polar and basic
Hydrogen Bonds
a weak attraction between a hydrogen atom and a partially charged negative atom (ex. between water molecules)
Hydrophilic
(lovesss waterr) mix with water (ex. NaCl, glucose)
Hydrophobic
(scared of water) does not mix with water (ex. CO2, O2)
Cohesion (think of astronaut video)
waters ability to stick to itself due to hydrogen bonds
Adhesion
waters ability to stick to polar and charged molecules
Heat Capacity
amount of energy it takes to change the temp of H2O so there are no large temp fluctuations
IMPORTANT for aquatic organisms
Water’s Heat Capacity
water has a high heat capacity which means it can hold a lot of heat without undergoing significant temp change due to the hydrogen bonds sticking together and stopping the molecules from moving faster
Heat of Vaporization
amount of heat needed to turn a liquid into a gas
Thermoregulation
how organisms maintain their body temperature within a healthy range.
How does Heat Of Vaporization help with thermoregulation?
sweating releases water onto the skin, as the water evaporates, it takes a lot of heat away from the body because of water’s high heat of vaporization.
This loss of heat cools the body down, helping to prevent overheating.
Transpiration
process by which water moves through plants and evaporates from small pores in the leaves, called stomata
How do cohesion and adhesion play a role in transpiration?
cohesion: allows water molecules to move up the tree
adhesion: prevents back-flow of water
Surface Tension
caused by a lack of water molecules at the surface to bond. higher intermolecular forces at surface
What does water do as a solvent?
water will dissolve ionic and polar molecules
Why does ice float on water?
because it’s less dense than water
Ice properties
has a stable, ordered structure, making it less dense and solid
Carbon
- 4 valence electrons
- allows for creating macromolecules
- found in all organic molecules
Carbohydrates
contains C, H, O and used for energy and makes up the cell wall for plants ad prokaryotes
are carbs polar or non polar
polar bc they dissolve in water
Lipids
made of C, H, O and are non - polar
Proteins
C, H, O, N and “S” - also are polar
Nucleic Acid
C, H, O, N, and “P” - polar that is why DNA stays inside the nucleus
How do we build large molecules?
involves the process of joining smaller molecular units, called monomers, into larger structures called polymers.
How are monomers and polymers synthesized?
Dehydration Synthesis and hydroylisis
Dehydration Synthesis
building polymers with the removal of water
Hydrolysis
splitting/breaking down polymers with the addition of H2O
Hydroxyl Groups
polar - OH
Carbonyl Groups
polar - C = O
Carboxyl Groups
polar - COOH
Amino
polar - N
Sulfhydryl
Polar - SH
Phosphate
polar -POOO
Methyl
non polar - C
Importance of functional groups
- influence the way a macromolecule reacts
- influences interaction with water
Elements in Carbs
C, H, O
What are the monomers of carbs?
monosaccharides
Monosaccharides
glucose, fructose, galactose
glucose, fructose, and galactose can also be calle
hexose, 6 carbon sugars
Alpha Glucose
below the ring (OH below)
beta glucose
above the ring (OH above)
Ribose Deoxyribose
pentose sugar - 5 carbon sugar
How do fructose, glucose, and galactose differ?
in their shape not their writing formula
Disaccharides
2 monosaccharides bonded together by dehydration synthesis - glycosidic bond
glucose + glucose =
maltose (disaccharide)
glucose + fructose =
sucrose (disaccharide)
glucose + galactose =
lactose + H2O (disaccharide)
Polysaccharides
3 or moe monosaccharides bonded together - starch, glycogen, and cellulose
Starch
stored form of of sugar in plants
glycogen
stored form of sugar in mammals
cellulose
make up cell wall of plants
What is the function of carbs?
to provide energy and used as a cell wall
To split a polymer into a monomer you use
Hydroloysis
To make a monomer into a polymer you use
Dehydration synthesis
Lipids
- contain the elements C, H, O; non-polar, ratio of hydrogen is greater than 2:1
Types of lipids
- triglycerides
- phospholipids
- steroids/ sterol
Triglycerides
Structure: A triglyceride is made of one glycerol molecule and three fatty acids.
How are triglycerides formed?
through dehydration synthesis, where water is removed to bond the fatty acids to glycerol
Saturated Fats
no double bonds and are solid at room temp
Unsaturated fats
1 or more double bond and liquid at room temperature
Ester Bonds
connect 3 fatty acids to the glycerol
Phospholipids
Made of two fatty acids, a glycerol, and a phosphate group
The fatty acid tails are (non-polar or polar)
hydrophobic - non - polar
The phosphate head is (polar or non- polar)
hydrophilic - polar
The phosphate head and the fatty acid tails are connected by
glycerol (3 carbon sugar)
Steroids/Sterols
Steroids have a structure of four carbon rings fused together.
what are examples of Sterols/Steroids?
cholesterol, testosterone. and estrogen
What are the functions of lipids?
protection, temp regulation, and they make up the cell membrane
Proteins
the elements are C, H, O ,N and sometimes S
the monomer is amino acid
the polymer is polypeptide
the shape of the protein determines the function
What proteins contain sulfur?
cysteine and methionine
Amino Acids can be buffers so that means that they can
donate and accept or pick up H’s
What is the bond between amino acids called?
a peptide bond
Primary Structure of a Protein Structure
the sequence of amino acids in a polypeptide chain; in charge of the order of the amino acids coded for by the DNA
Secondary structure of a protein structure
two types
- alpha helix
- beta pleated sheets
These shapes form due to hydrogen bonding between parts of the backbone
Tertiary Structure
The R groups interact with each other, causing the protein to fold into a specific shape.
These interactions can include
hydrogen bonds,
ionic bonds,
hydrophobic/hydrophillic interactions,
covalent bonds -disulfide bridges.
Amphipathic
contains both polar and non-polar regions
Quaternary Structure
2 or more polypeptides combined
A red blood cell is made up of
3 different polypeptides
Polypeptides
Chains of amino acids linked together by peptide bonds
Structure and Function of proteins
- the shape (conformation ) of proteins determines its function
- charges/R- groups determines interactions with other molecules
What are the function of proteins?
- muscle ( contractions and growth )
- antigens/ antibodies
- receptors
- enzymes are going to speed up chemical reactions
What is another name for enzymes?
catalyst
Mutations
if one or more DNA base is changed, this can change the RNA strand which can change the amino acid which can change the protein
What are the two types of proteins?
Globular and Fibrous
Globular
these are the doers and they carry out the chemical processes (ex. enzymes that speed up chemical reactions)
Fibrous
these are structural proteins (make up cytoskeleton which is essential in the cell wall) (ex. collagen)
Enzyme
sped up chemical reactions
Substrate
binds to enzyme (what the enzyme works on)
Active site
location where substrate binds to enzyme
Enzyme Substrate Complex
when the enzyme + substrate are bound ( they connect )
Lock and Key
1 substrate fits 1 enzyme perfectly
Induced Fit
when the substrate binds, the enzyme changes shape to make a tighter fit
What changes the shape of enzymes when it’s an induced fit?
electrochemical signals
Competitive Inhibition
a molecule that is similar in shape to the substrate which binds to active site and inhibits substrate from binding
Allosteric Inhibition
a molecule binds to Allosteric receptor and cause the active site to change shape which means the substrate cannot bind
What factors affect enzyme activity?
temp, pH, substrate/enzyme concentration
How does temp affect enzyme activity?
as temp increases, enzyme activity increases until optimal temp and then enzyme activity decreases
What happens when bonds in secondary structure and tertiary structure break?
the protein can refold because the primary structure isn’t changed
How does pH affect enzyme activity?
At pH levels too high (too basic) or too low (too acidic), the enzyme’s structure is altered, reducing or stopping its ability to work.
pH
the measure of how acidic or basic something is
What effect does the enzyme/substrate concentration have on enzyme activity?
as substrate concentration increases, enzyme activity increases and then levels off
What is the function of nucleic acids?
stores our hereditary information and then transmits hereditary information; codes for the production of proteins
What elements are nucleic acids made up of?
C, H, O, N, P
What is the monomer and polymer of nucleic acids?
monomer - nucleotide
polymer - nucleic acid/ DNA/ RNA
Nitrogenous Base
- adenine
- thymine
- cytosine
- guanine
Nucleotide Composition
- phosphate group
- pentose sugar
- nitrogenous base
pyrimidine
Cytosine
Thymine
Purine
Adenine
Guanine
When cytosine pairs with guanine how many hydrogen bonds are there?
3 hydrogen bonds
When adenine pairs with thymine how many hydrogen bonds are there?
2 hydrogen bonds
phosphodiester bond
the strong covalent bond that links one nucleotide to the next. It forms between the phosphate group of one nucleotide and the sugar of the next nucleotide.
Central Dogma
DNA gets turned into RNA which gets turned into proteins; DNA codes for the production of proteins
What is the difference in sugars in RNA and DNA?
DNA contains deoxyribose and RNA contains ribose
What is the key difference between deoxyribose and ribose?
ribose has an extra hydroxyl group (−OH) attached to the 2’ carbon of the sugar ring, while deoxyribose lacks this −OH group and instead has just a hydrogen atom (H) at the 2’ carbon.
