Exam 1 Biology 1 UTD Flashcards
What is the framework of most biological molecules?
Carbon bonded to other carbon molecules, or other types of atoms
What are hydrocarbons and their characteristics?
Covalently bonded hydrogens and carbons with nonpolar properties (Bonds have considerable energy)
What are functional groups?
Small, reactive groups of atoms that give larger molecules specific chemical properties
Name the different functional groups (Covalently bonded):
6 groups - hydroxyl, carbonyl, carboxyl, amino, phosphate, sulfhydryl
What is a hydroxyl group?
H-O, enables an alcohol to form linkage with other organic molecules through dehydration syntheses reaction
What is a carbonyl group?
C=O, are major building blocks of carbohydrates & participate in rxns supplying energy for cellular activity
What is a carbonyl group - aldehyde?
C=O that are @ ends of carbon & needs an H to complete
What is a carbonyl group - ketone?
C=O that is in the middle of molecules
What is a carboxyl group?
COOH, O=C-OH, gives organic molecules acidic properties because OH group readily releases the H+ proton, converting it from non-ionized to ionized form
What is the amino group?
NH2, H-N-H, acts as an organic base by accepting H+ proton for a full octect with a (+) charge converting from non-ionized to ionized form (NH2->NH3)
What is a phosphate group?
PO4, weak acids becuase the OH groups readily release their H+ protons in aqueous solutions, converting from non-ionized to ionized
What is a sulfhydryl group
S-H, easily converted into a covalent linkage by losing hydrogen atoms forming a DISULFIDE LINKAGE (S-S & 2H+)
What are isomers?
Molecules with the same molecular or empirical formula, but different chemical structures
Name the different kinds of isomers:
structural, stereoisomers, and enantiomers (a subcategory of stereoisomers)
What are structural isomers?
Same chemical formula but arrangement of atoms are different (the atom groups have moved within the molecule - different structure)
e.g. glucose - aldehyde, fructose - ketone
What are stereoisomers?
differ in how groups attached (atoms groups doesn’t move in the molecule)
What are stereoisomers - enantiomers?
mirror image molecules - chiral carbon (like your left and right hand: they look the same, but you can’t stack them)
Examples: L & D sugars
What are macromolecules
large organic molecules - carbohydrates, lipids, proteins, nucleic acids
What are monomers and polymers?
Monomers are chemically similar subunits that ultimately build polymers through dehydration synthesis
What is dehydration synthesis?
Formation of large molecules by the removal of water (Monomers joined to form polymers)
What is hydrolysis?
Breakdown of large molecules by the addition of water (Polymers broken down into monomers)
What ratio is present within carbohydrates?
- Molecules have a 1:2:1 ration of carbon, hydrogen, and oxygen (Good energy storage molecules)
- C-H covalent bonds hold much energy
- Examples: sugars, starch(polymer), glucose(monomer)
What is a monosaccharide
- Simplest carbohydrate composed of a basic six-carbon SUGAR (Enzymes that act on different sugars distinguish between isomers)
- C6H12O6 - glucose, fructose, galactose
- is a monomer
What is a structural isomer of glucose (aldehyde) C6H12O6?
Fructose (ketone)
What is a stereoisomer of glucose C6H12O6?
Galactose
What is the difference between alpha-glucose and beta-glucose?
There is carbon-one with hydroxyl group facing down (Alpha-glucose), or facing upwards (Beta-glucose)
What is the linear form of glucose?
Simple carbohydrate (C6H12O6) with carbonyl group (C=O) @ carbone-one & hydroxyl group (H-O) @ carbon-5
What are disaccharides?
- Two monosaccharides linked by dehydration synthesis (Used for sugar transport and energy storage)
- Is a polymer
- Examples: sucrose, lactose, maltose
Name the different disaccharide linkages and molecules:
a.) Maltose: two alpha-glucose molecules (Alpha 1->4 linkage)
b.) Sucrose: glucose and fructose molecules (Alpha 1->2 linkage)
c.) Lactose: glucose and galactose molecules (Beta 1->4 linkage)
What are polysaccharides?
- Long chains of monosaccharides linked through dehydration synthesis (Linear, or branched molecules)
- Energy storage (plants use starch [amylose], animals use glycogen)
- Structural support (plants use cellulose, anthropods and fungi use chitin)
Name the different polysaccharides:
Amylose (starch), glycogen, cellulose, chitin
What are the linkages and function of the polysaccharide amylose?
- A plant starch
- Energy storage
- Formed with α-glucose joined in chains (end to end) by alpha(1->4) linkages
What are the linkages and function of the polysaccharide glycogen?
- Found in animal tissues
- Energy storage
- Formed with α-glucose joined in chains & branches by alpha(1->4) and alpha(1->6) linkages
What are the linkages and function of the polysaccharide cellulose?
- Primary fiber in plant cell walls
- Structural support
- Formed with β-glucose joined in chains by beta(1->4) linkages
What are the linkages and function of the polysaccharide chitin?
- fiber win external skeleton of anthropods (insects) and fungi cell walls
- Structural support
- Formed from derivitives of glucose joined in chains by beta(1->4) linkages
What are the monomers of nucleic acids (DNA and RNA)?
- Nucleotides (Composed of sugar + phosphate + nitrogenous base)
- Connect nucleotides by phophodiester bonds
- Sugar is deoxyribose (D) in DNA or ribose (R) in RNA
From smallest to largest, how are nuleosides, nucleotides, and nucleic acids put in order?
Nucleosides (are in ->) nucleotides -> nucleic acids (DNA or RNA)
What bonds connect nucleotides?
Phophodiester bonds
What are nucleic acids?
Polymers made from Nucleotides (2 types = DNA and RNA)
What is a nucleoside?
A nitrogenous base + five-carbon sugar (Lacks the phosphate group)
Name the types of nitrogenous bases:
Pyrimidines: one carbon-nitrogen ring (Uracil or thymine, cytosine)
Purines: two carbon-nitrogen rings (Adenine, guanine)
What is the main difference between ribonucleotides and deoxyribonucleotides?
In the sugar, there is either hydrogen at carbon-2 (Deoxyribose) or a hydroxyl (OH) group (Ribose)
What is a phosphodiester bond?
Forms between the 5’ carbon (Phosphate group) of one nucleotide and the 3’ carbon (Sugar) of another
What does Uracil (U) look like?
A pyrimidine; 6 ring, no methyl group
What does thymine (T) look like?
A pyrimidine; 6 ring with methyl group on C2
What does cytosine (C) look like?
A pyrimidine, 6 ring with NH2 on C1 (instead of a ketone)
What does adenine (A) look like?
A purine, 6 ring connected to a 5 ring, NH2 on C1
What does guanine (G) look like?
A purine, 6 ring connected to 5 ring, ketone on C1 and amid on C5
What are ring-shaped sugars?
- 5-carbon deoxyribose in DNA or ribose in RNA
- The 2 sugars differ only in the atom group @ the 2’ carbon with hydrogen (H) in deoxyribose or hydroxyl (OH) in ribose
- In unlinked, the 5’ carbon can have 1-3 phosphate groups connected by phosphodiester bonds
Describe the function and structure of DNA:
- Encodes information for amino acid sequences of proteins
- Contains double helix (2 polynucleotide strands connected by hydrogen bonds)
- Sequences of bases (A//T or U, C///G)
- Backbone are held together by phohodiester bonds which link sugar to phosphate & at center are nitrogenous bases (A,G,U orT,C) bonded by a hydrogen
What is the difference in hydrogen bonds for the different complimentary base pairs?
Adenine and thymine have only 2 hydrogen bonds; guanine and cytosine have 3 hydrogen bonds
What is complementary base pairing?
Pairing of A—T or G—C to determine sequence of DNA (DNA replication uses these rules as a template)
Describe the structure and function of RNA:
- Single polynucleotide strand
- Uses information from DNA to sequence amino acids in proteins in ribosomes (DNA is like the headquarter and RNA are like the managers)
- Contains ribose
What are some other nucleotides?
a.) ATP: primary energy currency of the cell
b.) NAD+ and FAD+: electron carriers for many cellular reactions
What is ATP?
- Adenosine Triphosphate - ENERGY - is required for active transport
- Has an adenine nitrogenous base
- Has a ribo sugar
- Has the phosphate groups
What are some functions of proteins?
- Defense
- Enzyme catalysis
- Motion
- Regulation
- Support
- Storage
- Transport
What is the structure of proteins?
- Polymers composed of amino acids (Monomers) synthesized by dehydration synthesis to form chains of polypeptides connected by peptide bonds
- Unbranched
What is the basic structure of an amino acid?
Central C, amino group (NH2), carboxyl group (COOH), single H, and variable R group
What are the animo acid 4 classes?
- Nonpolar (hydrophobic)
- Polar uncharged (hydrophilic)
- Negatively charged
- Positively charged