Chapter 3 (Unit 1) Flashcards
What did chemists in the 19th century think about the molecules of cells?
That they must contain some vital force that helps the organism survive
What is organic chemistry?
Chemistry of organisms
What is inorganic chemistry?
The chemistry of nonliving world
What are organic molecules defined as?
MOlecules that contain both carbon and hydrogen atoms
What are the four classes of organic compounds in living things?
Carbohydrates, lipids, proteins, and nucleic acids
What are the class of organic molecules called?
Biomolecules
What facts about carbon explain it’s ability to make such diverse life?
- Can have four bonds
- bonds to CHNOPS
- The shape and function varies greatly
- Carbons can form double bonds
What element makes up the backbone of most molecules?
Carbon (carbon chains)
What is a functional group?
It is a specific combination of bonded atoms that always react in the same way, regardless of the carbon skeleton
Hydroxl: Structure, Compound, Significance
Structure: OH-R
Compound: Alcohol as in ethanol
Significance: Polar, forms hydrogen bond, present in sugars and some amino acids
Carbonyl: Compound, Significance
Aldehyde (as in formaldehyde), Ketone (acetone).. Polar (present in sugars)
Carboxyl: Compound, Significance
Carboxylic acid (acetic acid), Polar, acidic, Present in fatty acids and amino acids
Amino
Amine (tryptophan), Polar, basic forms, hydrogen bonds, present in amino acids
Sulfhydryl: Compound, Significance
Thiol (as in ethanethiol), Forms disulfide bonds, present in some amino acids
Phosphate: Compound, Significance
Organic phosphate, as in phosphorylated molecules, Polar, acidic, present in nucleotides and phospholipids
What is hydrophobic?
It means “not soluble in water”
What is hydrophyllic?
Means soluble in water
What do the attached functional groups determine about the molecule?
They determine the polarity of the organic molecule and the types of reactions it will undergo
WHat are isomers?
They are organic molecules that have identical molecular formulas but vary in different arrangement of atoms
How are isomers going to differ in chemical reactions?
Isomers have different structures and functional groups. Therefore, they will behave differently in chemical reactions
What is dehydration synthesis?
It is the process by which a cell uses condensation to synthesize any type of biomolecule. An OH- is released from one group and a H+ is released from another and the two subunits are joined
What his hydrolysis?
It is the process that the cell uses to break apart biomolecules. An OH- and H+ come back and attach to the ends of the two subunits, respectively
What is required for a cell to carry out a dehydration and hydrolysis?
An enzyme
What are polymers?
They are the largest of biomolecules
What makes up polymers?
Monomers (the subunits)
What are carbohydrates used as?
An energy source in living things. However, they also play a structural role in organisms
What are monoscaccharides?
They consist of a single sugar molecule and are called simple sugars
How many carbons usually make up the backbone of a simple sugar?
3-7
What is the molecular formula of a simple sugar?
CH2O
How many carbons does glucose have, and what is it’s molecular formula?
C6H12O6
What are some of the isomers of glucose?
fructose and galactose
WHere are Ribose and Deoxyribose found, respectively?
They are found in the nucleic acids RNA nad DNA
What is a disaccharide?
It consists of two monosaccharides that have been joined together via dehydration synthesis
What are polysaccharides?
They are polymers of monosaccharides
How do plants store glucose?
Starch
How do animals store glucose?
as glycogen
Are polysaccharides soluble in water?
No
What are the structural polysaccharides?
Cellulose (in plants), chitin (in animals and fungi), and peptidoglycan (in bacteria)
Where is cellylose fond?
In plant , it is used also in many products.
Where is chitin found?
It is found in fungal cell walls as well as the exoskeletons of many insects
What are lipids?
They are compounds that are insoluble in water dueo the the hyrocarbon chains
Why are compounds that have hydrocarbon chains insoluble?
This is because the hydrogens bonded to carbon have no tendency to form hydrogen bonds
What two subunit molecules do Fats and Oils contain?
fatty acids and glycerol
What is a fatty acid made up of?
Hydrocarbon chain with a carboxyl at the end. There are approximately 16-18 carbons per molecule
What is the difference between saturated fatty acid and unsaturated fatty acids?
Saturated fatty acids have no double bonds between the carbon atoms. Unsaturated fatty acids have double bonds in the carbon chain.
What is glycerol made up of?
It is a compound with three OH- groups. They are polar molecules
When a fat or oil forms, what is the raction that occurs?
Dehydration Synthesis.
Why are fats and oils sometimes called triglycerides?
There are three fatty acids attached to one glycerol molecule
Why do triglycerides with unsaturated fats melt at a lower temperature?
Because the double bond prevents too much packing between the hydrocarbons so it melts faster
Is butter a saturated fat, or an unsaturated fat?
it is a saturated fat
Why do almost all animals use fat as opposed to glycogen as long term storage?
This is because per gram, fat an contain more energy
What is the function of fats?
Long term energy storage and insulation in animals (Butter, lard)
What is the function of oils?
Long term energy storage in plants and their seds
What is the funtion of phospholipids?
They are a component of plasma membrane
What is the function of a steroid?
They are a component of the plasma membrane (cholesterol), sex hormones
What is the function of wax?
For protection, to prevent water loss (cuticule of plant surfaces), beeswax and earwax
How is a phospholipid constructed?
Like a fat, except in the place of the third fatty acid, there is a polar phosphate grou.
What does the phosphate group become?
It becomes the polar head
How do the phospholipids arrange themselves?
They arrange themselves so that the polar heads are adjacent to a water medium
What are steroids?
They are lipids that have skeletons of four fused carbon rungs
How do steroids differ from eachother?
They differ based on the types of functional groups attached to the carbon skeleton
What two things bond together to form a wax?
Long chain fatty acids bond with long chain alcohols
The plasma membrane that surrounds a cell contains what?
A phospholipild bilyer. The kinks in the membrane cause the membrane to be fluid
What are some of the functions of proteins?
Metabolism, Support, Transport, Defense, Regulation,Motions
Describe: Metabolism
Enzymes bring the reactant together and speed chemical reactions in cells. The enzyme is reactant specific
Describe: Support
Many proteins are responsible for structure,s uch as collagen, keratin
Transport: Describe
Channel and carrier proteins in the plasma mebrane allow substances to enter and exit cells. Others, transport molecules in the blood (such as hemoglobin)
Defense: Describe
Antibodies are proteins that combine with foreign substances called antigens. They prevent antigens from destroying cells and upsetting homeostasis
Regulation: Describe
Hormones are regulatory proteins. They serve as intercellular messengers that influence the metabolism of cells. One example of this is insulin,w hich regulates the content of glucose in the blood
Motion: Describe
The contractile proteins actin and myosin allow parts of cells to move and cause muscle to contracts. All cells contain a protien that allow them to move from place to place
What are the monomers of a protein?
Amino acids
Dehydration synthesis occurs in proteins between _______
carboxyl group and the amino group
The covalent bond between two amino acids is called.”
Peptide bond
What is a peptide?
It is two or more amino acids bonded together
What is a polypeptide?
It is a chain of many amino acids joined by peptide bonds. A protein could contain more than one polypeptide chain
Why is the name amino acid very appropriate?
Because there is an amino acid and an acid group
What “groups” are there in an amino acid?
An R Group, An acid group (-COOH), An Amino group (-NH2)
How many total levels of structure can a protein have?
4
What is primary structure?
The level of structure is determined by the sequence of amino acids that join to forma polypeptide
Secondary Structure (of protein)
- It occurs when polypeptide coils or folds in a particular way
- Can coil in either an alpha helix or a beta sheet
- Hydrogen bonding occurs to hold the secondary structure of a polypeptide in place
What is an example of a secondary structure protein?
keratin
Describe a tertiary structure
They are called globular proteins and have round shapes. Hydrogen bonds, ionic bonds, covalent bonds all help the structure. Disulfide bonds play a key role in keeping the protein together
What kind of proteins are enzymes?
They are globular protiens
What is the term that describes when a protein loses it’s natural shape?
Denature
What is quaternary structure?
They consist of more than one polypeptide
What is a big example of quaternary proteins?
Hemoglobin
What are nucleic acids?
They are polymers of nucleotides with very specific functions in cells
What is DNA?
It is the nucleic acid that stores genetic information regarding it’s own replication and the order in which amino acids are to be joined to make a protein
What does RNA do?
It is another type of nucleic acid. It helps synthesize DNA/proteins
What is a nucleotide made up of?
Phosphate, pentose sugar, nitrogen containing base
What are the pyrimidines?
They are cytosine and thymine
What are the purines?
Adenine and Guanine
What is adenosine composed of?
Adenine and ribose
What does ATP usually break into?
ADP and Phosphate
