Chap 2 Chemistry And Biochem Flashcards
Biochemistry
Chemical composition and reactions of living things
Types of chemicals in the body
Organic
Inorganic
Organic compounds
Have carbon
Made by living things
Types of bonds in all organic compounds
Covalent
Usually large
Inorganic compounds
Don’t have carbon
Examples of inorganic compounds
Water, salts, acids, bases
Exceptions of inorganic compounds
CO2 & CO
Have carbon but considered inorganic
T o F Both organic and inorganic compounds are important?
True
Water makes up what volume of living things?
60-80%
Most abundant and important inorganic compound?
Water
What properties make water special?
1.High heat capacity
2.High heat vaporization
3. Polar solvent properties
Why is high heat capacity useful?
Prevents changes in temperature. Takes a lot of energy to change it’s temperature so it’s good at maintaining stable conditions.
Why is high heat of vaporization useful?
Takes a lot of energy for water to evaporate. Helps cool when sweat. Our body releases large amounts of energy to make sweat evaporate, cooling us off in the process
Why are polar solvent properties useful?
Biological molecules don’t react unless they’re in solution. All reactions in the body depend on water’s solvent properties. Good at attracting molecules and surrounding them
Can transport things
Hydration layers
Layers of water molecules around large charged molecules. Protects from other charged molecules & prevents them from settling out of solution.
Biological colloids
Protein water mixtures
Blood plasma
CSF
Importance of Reactivity in water
Water is an important chemical reactant in many reactions. Breaking down food molecules through hydrolysis
Importance of water’s cushioning
Not compressible but it can flow. Form cushions around organs. Protects from trauma. CSF
Salt
Ionic compound. Has cations other than H+
Anions other than OH-
Dissociates into components
Electrolytes
Substances that conduct electrical currents when in solution.
All ions
Examples of common salts in the body
NaCl,
CaCO3
KCl
Most plentiful salts in body
Calcium phosphates that make bones and teeth hard
What are salts good for?
Na &K ions important for muscle contractions
Fe ions make hemoglobin
Zn and Cu maintain enzyme activity
Are acids and bases electrolytes?
Yes they dissociate and can conduct electrical currents
Acids properties
Dissolve metals, sour taste. Releases H+ ions
Proton donor because H+ is only proton
What determines the acidity of a solution?
H+ concentration
What’s a good way to recognize the formula for an acid?
It will have an H in the beginning
Bases properties
Bitter taste, feel slippery, proton acceptors
Common inorganic bases
Hydroxides, dissolve in water but liberate OH- and cations
Bicarbonate ion importance
Important base in body, abundant in blood
What does Ammonia do?
Base.Common waste product of protein breakdown in body.
Attracts protons with it’s one pair of unshared electrons. Ammonia becomes ammonium
What do pH units measure?
Relative concentration of H ions in body fluids
Each change of pH represents a ____X change in H+ concentration
10
Formal definition of pH
Negative log of H+ concentration in Moles/Liter
When is a solution neutral
pH=pOH
life preserving enzymes in body work within narrow pH range. T or F
True
Buffers
Resist abrupt and large swings in pH of body fluids by releasing and binding H as needed
What are buffers made of ?
Weak acid, weak base
Explain the bicarbonate buffer system
- Carbonic acid dissociates into bicarbonate and a proton
- When blood pH lowers (more acidic) bicarbonate binds H+
when blood pH is higher carbonic acid releases H
Strong bases are turned to weak bases and protons are bound to make weak acids
Electroneutral
Never loses or gain electrons
Why is carbon’s electroneutrality important?
Makes 4 covalent bonds, can make long chains, never loses or gains electrons
Can make various different shapes
Macromolecules
Complex molecules containing thousands of atoms.
Which process binds monomers?
Dehydration synthesis
Explain dehydration synthesis
- A Hydrogen is removed from one monomer and a hydroxyl is removed from the monomer that it will be joined with. A water molecules is removed from the bond site each time more monomers bind
Hydrolysis
Molecules split using water
Functional groups
Parts of organic molecules where reactions occur.
What percentage of cell mass are carbs?
1-2%
Ratio of H and O in carbohydrates
2:1
Hydrated carbon
Ways to classify carbohydrates
Size and solubility
Classification by size
Monosaccharide
Disaccharides
Polysaccharides
What is more soluble in water monosaccharide or polysaccharide?
Monosaccharide..
Bigger molecules are less soluble
Monosaccharides
Single ring or single chain 3-7 carbon atoms
Ratio of monosaccharides and formula
1:2:1
(CH2O)n
n= number of carbons in the sugar
Which monosaccharides are most important in the body?
Pentose and hexose
Example of pentose
Deoxyribose
Example of hexose
Glucose
Isomers
Same formula, different arrangement so different chemical properties
Examples of isomers of glucose
Galactose
Fructose
Disaccharides
Double sugars
Formed by dehydration synthesis
Disaccharides
Sucrose
Lactose
Maltose
Sucrose
Glucose + fructose
Cane sugar
Can disaccharides go through cell membrane?
No must be hydrolysed to monosaccharides
Polysaccharides
Polymers of simple sugars
Storage
Important polysaccharides
Glycogen
Starch
(Polymers of glucose)
Starch
Storage carb made by plants
Found in grains and potatoes
Cellulose function
Not digested
Bulk of fiber
Glycogen stored in
Liver and skeletal muscle
How is glycogen used?
Muscles use it to move
Liver uses it to maintain blood sugar. Let’s body cells get fuel
Carbohydrates roles
Ready, easily used source of fuel
Most cells can only use simple sugars like glucose
Lipids dissolve in
Other lipids sand alcohol and ether
Amount of oxygen in lipids is higher or lower?
Lower
Triglycerides
Major form of stored energy in the body
Fat deposits in subcutaneous tissue and around organs. Protect and insulate organs.
Phospholipids
Chief part of cell membrane
Transport lipids in blood. Part of lipoproteins
Types of steroids
Cholesterol
Bile salts
Vitamin D
Sex hormones
Corticosteroids
Cholesterol
Component of all cell membranes
Starts synthesis of all body steroids
corticosteroids
cortisol
aldosterone
Bile salts
Made by breakdown of cholesterol,
released by liver into digestive tract to help with fat digestion and absorption.
Vitamin D
Made in skin after UV radiation touches skin
Needed for bone growth and function
Sex hormones
Estrogens and progesterone
made in gonads
cortisol
maintains glucose levels
Aldosterone
regulates salt and water balance, targeting kidneys
Fat soluble vitamins
ADEK
Eicosanoids
prostaglandins and thromboxanes
made from fatty acids found in all cell membranes
Prostaglandins
functions
promote inflamation
stim. contractions
regulate BP
controlling GI movement
Blood clotting
Thromboxanes
powerful vasoconstrictors
Lipoproteins
Lipid and protein based substances, transport fatty acids and cholesterol in blood
Major kinds are High density and Low density
Glycolipids
Parts of Cell membranes
Carbs attached to lipids determine blood type.
help cell recognition and recognition of foreign substances
Triglycerides are known as ____ when solid
fats
Triglycerides are known as ___ when liquid
oils
Most efficient and compact form of stored energy?
Triglycerides
When do triglycerides yield large amounts of energy?
When oxidized
Building blocks of triglycerides?
Three fatty acids and a glycerol
Fatty acids
Hydrocarbon chains that end with COOH
Glycerol
modified simple sugar (sugar alcohol)
Why do fats have to be broken down to absorb?
Oil and water don’t mix. Ingested fats and oils must be broken down to their building blocks. Polar and nonpolar don’t interact.
Why are woman better english channel swimmers?
The fat helps insulate them from cold water
Saturated fats
single covalent bonds
straight chains
solid at room temp because closely packed
Unsaturated fats
one or more double bonds (mono or poly unsaturated)
kinked chains, can’t solidify.
More heart healthy
Trans fats
oils that are solidified by adding H at carbon double bonds. Increase heart disease risk
Omega 3 fatty acids benefits
Decrease risk of heart disease and inflammatory diseases
Difference between phsopholipids and triglycerides
2 fatty acids and a phosphate
Steroids structure
flat, four interlocking hydrocarbons. Fat soluble, little oxygen
Most important molecule in steroid chemistry
Cholesterol
Sources of cholesterol?
eggs, meat, cheese, liver
Atherosclerosis
Fat buildup in walls of arteries
NSAIDS
Non steroidal anti-inflammatory drugs, ibuprofen. Block actions of prostaglandins
Percentage of proteins in cell mass?
10-30%
basic structural material of body
proteins
Structural proteins
mechanical support, example, collagen most abundant protein in body
Enzyme proteins
needed for all biochemical reactions. disaccharidases hydrolyze disaccharides, proteases hydrolyze proteins. oxidase oxidizes food fuels
transport proteins
move substances in blood or across membrane. Hemoglobin or transport proteins in cell membrane.
Contractile proteins
movement
actin and myosin cause muscle contraction. help during cell division
Communication proteins
transmitting signals between cells. Cheical messengers. Insulin
Defensive proteins
protect against disease. Antibodies bind and inactivate foreign substances
building blocks of proteins
aminoacids
Parts of aminoacids
Amine group and acid group
t/f amino acid can act as base or acid
true
what makes aminoacids chemically unique?
R groups
elements in aminoacids
CHON 2 have S
How do aminoacids bind?
dehydration synthesis, the amine ends and amino acid groups are bound.
peptide bond
joins aminoacids
binds carboxyl group to amine group. loss of h2o
polypeptide
10 or more aminoacids bound
how many common aminoacids?
20
Primary structure of proteins
Amino acid chains. linear sequence of aminoacids
secondary structure
alpha helices or beta pleated sheets
tertiary structure
secondary structures are folded to globular form. Involves R groups on secondary structure are attracted to eachother
quartenary structure
Two or more polypeptides with tertiary structure combine
most common type of secondary structure
alpha helix. Stabilized by hydrogen bonds between NH ans CO. Link different parts of same chain together
T/F Beta pleated sheetscan be made of different polypeptides
T?
Transthyretin
transports thyroid hormone
What determines the structure of a protein
its primary structure
positions of hydrophillic and hydrophobic aminoacids in proteins
hydrophillic near surface, hydrophobic in core
Most abundant protein in body
collagen
characteristics of fibrous proteins
contractile some
insoluble in water
Functional proteins characteristics
globular; compact sphereical, have at least tertiary structure, water soluble, chemically active. immunity, hormones, transport
Are globular proteins stable or unstable?
unstable
What causes hydrogen bonds to break?
low pH
High temp
Denatured proteins
Proteins unfold because hydrogen bonds due to changes in pH or temperature
irreversibly denatured
protein can’t go back to original form. Chaneg in conditions too extreme. Scrambled egg
active sites
regions that fit and interact chemically with other complimentary molecules.
How can enzymes be destroyed?
active site destroyed through denaturation because of extreme changes.
Can enzymes force molecules to react?
NO
apoenzyme
protein portion of an enzyme
cofactor
metal ion or organic molecule needed for enzymatic activity
holoenzyme
apoenzyme+cofactor
Substrate
Substance an enzyme acts on
catalytic activity happens at
active site
are enzymes chemically specific?
yes, certian enzymes only bind to certain chemicals or certain groups of chemicals
Do enzymes require activation?
some of them, this keeps enzymes from functioning where they’re not supposed to
Activation energy
amount of energy needed for reaction to occur
When do you need activation energy?
for all reactions, regardless of endergonic or exergonic
How do enzymes speed up reactions?
By lowering the activation energy needed to function
Explain the mechanism of enzyme activation
E+S-> E-S ->P+E
- active site changes shape to bind substrate
- ES complex rearrages internally to make products. then returns to original shape
- Enzyme can catalyze millions of times within a minute
Enzyme inhibitor
subtance shaped like substrate blocks binding site
Which example of protein structure involves interactions between the R-groups of distantly positioned amino acids along the polypeptide chain?
tertiary structure
Which bonds within ATP are considered “high-energy”?
-phosphate -phosphate
bond between 2nd and third phosphate groups gives energy transferred to other molecules during cellular work
largest molecules in the body?
nucleic acids DNA RNA
DNA
in nucleus, genetic material, genome
Roles of DNA
Replicates
Instructions for building every protein
Major cellular site of RNA
Cytoplasm
Major functions of RNA
genetic instructions for protein synthesis
Structure of RNA
single strand, straight or folded
sugar in RNA
ribose
Bases in RNA
AG CU
Major cellular site of DNA
Nucleus
structure of DNA , sugar, bases
doublehelix, deoxyribose, AG CT
uses of DNA
fingerprinting, paternity tests, crime identification of body
molecular slave of DNA
RNA except for viruses where rna is the main genetic material
Types of RNA
rRNA
tRNA
mRNA
microRNA
Small RNA molecules
nucleotides
structural units of nucleic acids
Parts of a nucleotide
nitrogen containing base, pentose sugar
phosphate
purines, larger double ringed
adenine and guanine
Pyrimidines, smaller, single ring
Cytoside, thymine, uracil
backbone of DNA
Alternating sugar and phospahtecomponents
A bonds to
T
G bonds to
C
U replaces
T
Primary energy transferring molecule
ATP
Phosphorylation
Passing the P from ATP to another molecule
Most important cellular fuel
Glucose
Structure of ATP
RNA nucleotide with two more phosphates
What lets ATP store energy?
3 negatively charged phosphate groups repel eachother
What happens after phsphorylation?
Molecules more active, can perform cellular work. after they do the work they lose the phosphate. energy released by phosphate is close to activation energy. chemical work, mechanical work, transport work
Acidosis
blood pH below 7.35
Alkalosis
pH higher than 7.45.
heavy metals toxic
arsenic, mercury, and lead. Iron, also included in this group, is toxic in high concentrations.
ionizing radiation
causes atoms to ionize, gamma rays, xrays
Radiation sickeness,
disease caused by radioactivity. Rapidly dividing cells are most affected. blood forming cells and digestive tract cells most affected
Make 90% of elements in body by mass
CHON
Phosphorus
Calcium phosphate in bones
ATP
Potassium
Dissolved electrolyte in blood plasma
Sulfur
Protein folding
Cystine
Make disulfur bridges to shape proteins
Na
Electrolyte for depolarization to pass on potentials
Trace elements
If it looks like a metal,
Help proteins fold like hemoglobin.
For every proton there is
An electron
Mass of protons and neutrons
1 amu
Isotopes
Same number of protons , dif number of neutrons
Kalemia
Potassium
Iodine is used in
Hormones made by thyroid
Which type of compound contains carbon and hydrogen?
Organic
Atoms
Smallest part of an element. Has components like electrons, protons, neutrons
Elements
Pure substance that cannot be broken down into simpler substances
Molecules
2 or more atoms held together by chemical bonds
Same element
Compound
Made by 2 or more different types of elements
