BIO 101 EXAM 1: Chapter 2 (Structure and Function of Macromolecules )
How are two monosaccharides joined? What forms when they are chemically joined?
- When two monosaccharides are joined together, they form a disaccharide. - They are joined together by a dehydration reaction. One monomer gives up a hydroxyl group and the other gives up a hydrogen atom.
Characteristics of a saturated fatty acid
- a fatty acid that has no double bonds In its hydrocarbon chain has the maximum number of hydrogen atoms attached to each carbon atom - Most animal fats, lack double bonds/tightly packed, making them more solid at room temperature
What does the word hydrophillic mean?
"Water loving"
Hydrolysis
(breaks down polymers into monomers) Process of digestion in which the bond between monomers is broken by the addition of a water molecule, with the hydroxyl group from the water attaching to one monomer and a hydrogen attaching to the adjacent monomer
Characteristics of an unsaturated fatty acid
- A fatty acid whose hydrocarbon chain contains one or more double bonds. - Generally found in fats of plants and fishes, usually liquid at room temperature - Each carbon atom connected by a double bond has one fewer hydrogen atom attached to it. - These double bonds usually cause kinks (or bends) in the carbon chain.
Phospholipid
- A major component of cell membranes - Polar, hydrophilic head - Nonpolar, hydrophobic tail
Primary structure of a protein
- Amino acids (monomers) joined together through a dehydration reaction (they are linear) -- Covalent bonds hold this structure together. These bonds are given a special name: Peptide bonds
How might a dispersant be useful in the human digestive system?
- Amphiphilic molecules like bile disperse fat into small droplets. - Lipid digesting enzymes can then hydrolyze the triglycerides into monomers for absorption into the gut.
Difference between carbohydrates and lipids in terms of water?
- Carbohydrates are hydrophilic - Lipids are hydrophobic
What do we call it when a protein unravels or unfolds? What happens to its function?
- Denaturation - It no longer functions
Nonpolar covalent bonds Examples?
- Electrons shared equally - Carbon and Hydrogen
Why do plants use starch for energy storage whereas animals use fats ?
- For plants, the bulkiness of starch is not a problem for immobile plants. - For animals, it is much easier to get around when carrying their food reserves in the form of fat
quarternary structure of protein
- Proteins with more than one polypeptide chain - The shape results from the association of two or more polypeptide subunits - Not all proteins have quaternary structure - Held together by R groups
Food contains macromolecules - why do we eat food? (plants and animals)
- Raw organic material for building our own macromolecules (to replenish dead cells and grow) - Energy for cellular work
Covalent bond how strong? what are the two types?
- Share electrons (1,2, or 3 pairs) - Can be VERY strong - Two types: Nonpolar and polar
What do anabolic steroids mimic in the body and what effects do they have?
- They structurally resemble testosterone - Effects: Violent mood swings, depression, liver damage or cancer, and high cholesterol levels and blood pressure - Use of these drugs often makes the body reduce its output of natural male sex hormones, which can cause shrunken testicals, reduced sex drive, infertility, and breast enlargement.
What are the monomers of a triglyceride (fat) molecule ?
- Three fatty acids and one glycerol
What does the R group do?
- distinguishes one amino acid from another - The folding of different R groups determines the characteristics (size, polarity, and pH) for each type of amino acid
teritary structure of a protein What permits this structure?
- the overall three dimensional shape of a polypeptide due to interactions of the R groups of the amino acids making up the chain - Amino acids are near to each other because their R groups are allowing them to interact (imagine one positive charged and one negatively charged)
What are the four major classes of macromolecules?
1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids
What are the four levels of protein structure?
1. Primary 2. Secondary 3. Tertiary 4. Quaternary
All atoms of an element have the same _____________ but some atoms of that element may differ in __________
1. atomic number 2. mass number
What descent are most likely to be lactose intolerant?
African American, Native American, Asian American
So what makes the atoms of different elements different?
All atoms of a particular elements have the same unique number of protons --> This number is the element's atomic number
When proteins fold incorrectly they can cause disease. Which diseases?
Alzheimer's, Parkinson's, and Mad Cow Disease
What is an atom?
An atom is the smallest unit of matter that still retains the properties of an element
structural polysaccharides
Give structure to plants
Ionic bond
Formed when one or more electrons are transferred from one atom to another
Which one of these is an organic compound? Water Carbon dioxide Glucose
Glucose
Characteristic of a trans fat?
They do have double bonds, however, a chemical process that converts unsaturated fats into trans fats straightens them out.
What are lactose intolerant people missing?
They lack the enzyme lactase, which helps break down the bond in sugar (lactose) When people take a lactade, they are taking in this enzyme.
Comparison between unsaturated fat and trans fat
Trans fats have hydrogens on opposite sides of the double bond
dipeptide
Two amino acids bonded together
Unbranched versus branched structure
Unbranched structures consist of a single carbon chain. Branched structures have a substituent that is attached to a carbon on the chain.
What does the word hydrophobic mean?
Water-fearing
trans fatty acids
a kind of fat formed when hydrogen is added to vegetable oil during processing
Macromolecule
a molecule containing a very large number of atoms, such as a protein, nucleic acid, or synthetic polymer.
Electron
a subatomic particle with a single negative charge (-)
What are the monomers of proteins?
amino acids
What is an R group?
any group in which a carbon or hydrogen atom is attached to the rest of the molecule
An atoms atomic mass is
approximately equal to its mass number - the sum of its protons and neutrons - in daltons
Hydrogen Bonds Properties of this kind of bond? Example?
attraction between a slightly positive hydrogen (from a polar molecule) and a slightly negative atom (from a different polar molecule) WEAK Water molecule
Trans fats increase ____________ risk
cardiovascular
Detergent acts as an_________? What does this mean?
dispersant - Detergents surround oil in water and form a protective layer so that the oil molecules cannot "clump" together. The detergents "disperse" the oil into small droplets and in the water, such as when you use soap to wash an oily dish.
Of the three subatomic particles - protons, neutrons, and electrons - only __________ are directly involved in the chemical activity of an atom
electrons
It is the number of _________ present in the outermost shell, called the ___________, that mostly determines the chemical properties of an atom
electrons, valence shell
What are the three main types of lipids?
fats, phospholipids, steroids
What are the products of photosynthesis?
glucose and oxygen
Monomer of Phospholipids
hydrophilic head and two hydrophobic tails
only _________ can be absorbed into the intestine
monomers
What are the monomers of carbohydrates ? Examples?
monosaccharides (simple sugars) Glucose, Fructose, Dextrose, Hexose, Pentose
Cellulose
most abundant organic compound on earth - A structural polysaccharide found in plants cellular wall
What are the monomers of DNA?
nucleic acids
Atoms whose _______ are not full tend to interact with other atoms in ways that enable them to complete or fill their valence shells Atoms whose _________ are full will not interact readily with other atoms
outer shells ; outer shells
What causes denaturation?
pH and temperature (heat)
What are the four polysaccharides?
starch, glycogen, cellulose, chitin
storage polysaccharides
storage form of energy,
Neutron
Electrically neutral (has no charge)
Covalent bond
A chemical bond that involves sharing a pair of electrons between atoms in a molecule
Dehydration Reaction
A chemical reaction in which molecules combine by removing water (which is lost to the environment) - Builds polymers from monomers
What is an organic compound?
A compound that contains carbon-based molecules (also usually contains hydrogen atoms)
Molecule
A group of atoms bonded together
Polymer
A long molecule consisting of many similar or identical monomers linked together.
Electronegativity
A measure of the ability of an atom in a chemical compound to attract electrons
Macromolecule
A molecule containing a very large number of atoms, such as a protein, nucleic acid, or synthetic polymer.
Polypeptide
A polymer (chain) of many amino acids linked together by peptide bonds.
Monomer
A simple compound whose molecules can join together to form polymers
Starch Examples in human diet ?
A storage polysaccharide in plants, consisting of long chains of glucose monomers. - Potatoes, grains, etc. - Can be branched or unbranched
Proton
A subatomic particle with a single positive electrical charge (+)
Dissacharides
A sugar containing two monosaccharides. Example: sucrose which is fructose + glucose.
Enzyme
A type of protein that speeds up a chemical reaction in a living thing
How big is a protein?
Anywhere from a few amino acids to several thousand
In photosynthesis, ________ and ___________ are the reactant
CO2 and H2O
Polysaccharides
Carbohydrates that are made up of more than two monosaccharides
Ionic bonds Example?
Electrons are not shared NaCl
Polar covalent bond examples?
Electrons are not shared equally creating "poles" - a slightly negative and slightly positive end Oxygen
What is the main function of fats?
Energy storage
The DNA sugar-phosphate backbone is held together by covalent bonds. What kinds of bonds hold the two strands of the double helix together?
Hydrogen bonds
Secondary structure of a protein
Hydrogen bonds hold secondary structure together between the amino end of one amino acid and the carboxy end of another amino acid.
amphiphillic molecules
Hydrophobic tails + hydrophilic heads
Explain how lactose tolerance involves three of the four major classes of biological macromolecules.
Lactose, milk sugar, is a carbohydrate that is hydrolyzed by the enzyme lactase, a protein. The ability to make this enzyme and the regulation of when it is made are coded in DNA, a nucleic acid.
The use of sugars as both energy resources and organic building blocks clearly illustrates one of our five themes of life:
Life depends on the transfer and transformation of energy and matter.
What might a mutation in one amino acid do to the structure of a protein?
Might cause it to change shape, might not likely depends on how the r groups interact
Glycogen
More highly branched than starch. A storage polysaccharide in animals which forms glucose from hydrolysis.
Marfan syndrome is an example of what?
Mutation in protein that affects the structure and function (affects the connective tissue)
Monosaccharides
Single sugar molecules
Think about making a necklace with small beads. Use the necklace as an analogy to use the words macromolecule, monomer, polymer, dehydration reaction, and hydrolysis in sentences.
So, you're making a necklace out of beads, to which we can refer to as macromolecules, as theyare the building blocks of life and make the necklace what it is. These specific macromolecules,or each individual bead, is a monomer, and after adding one to the string to create a necklace, you have one monomer. However, if you want to add multiple beads, you must use the dehydration reaction, where you add another monomer (bead) to create a chain of multiple monomers, otherwise known as a polymer. However, let's say you added the incorrect pattern and now the polymer (or section of beads), does not follow the correct pattern to create a functional, pretty necklace. From there, you can use hydrolysis to take apart the polymer back into the sections of monomers, and from there, you can fix the pattern for your necklace.
Chitin
Structural polysaccharide used by crustaceans and insects to build their exoskeleton, the hard case enclosing the animal. Chitin is also found in the cell walls of fungi.
There are 20 different amino acids, what part of each amino acid makes it different from the other amino acids?
The variable chemical group (R) - Some have large R groups, some have small R groups. - Others have hydrophobic R groups, or hydrophilic R groups, etc.
Cell membranes contain a phospholipid bi-layer with __________ parts in aqueous environments (outside and inside cell) and ____________ parts at the core.
hydrophillic; hydrophobic
The different _____________ of an element have the dame number of protons and behave identically in chemical reactions, but they have different numbers of neutrons
isotopes
A __________________ is one in which the nucleus decays spontaneously, giving off particles and energy
radioactive isotope
Atom's mass number
the sum of the protons and neutrons in an atom's nucleus
tripeptide
three amino acids bonded together
A protein's function is dependent on its ______.
unique shape