Biology Study Guide Chapter 3 Flashcards
Nucleotide
The building blocks of a nucleic acids, including DNA and RNA, phosphate group, a sugar, and a nitrogen-containing base.
DNA
Deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information- Web
DNA codes fro proteins- Notes
RNA
Ribonucleic acid, a nucleic acid present in all living cells. Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins, although in some viruses RNA rather than DNA carries the genetic information.
Amino Acid
A simple organic compound containing both a carboxyl (-COOH) and an amino (-NH2) group.
Protein
They perform the greatest amount of tasks in living organisms.
a) structural proteins, like hair nails.
b) Storage proteins, like in food.
c) Contractile proteins.
d) Trans protein.
Peptide Bond
The primary linkage of all protein structures; the chemical bond between the carboxyl groups and amino groups that unites a peptide
Monosaccharide
Any of the class of sugars (e.g., glucose) that cannot be hydrolyzed to give a simpler sugar.
Disaccharide
Any of a class of sugars whose molecules contain two monosaccharide residues.
Polysaccharide
A carbohydrate (e.g., starch, cellulose, or glycogen) whose molecules consist of a number of sugar molecules bonded together.
Condensation Reaction
The conversion of a vapor or gas to a liquid.
Hydrolysis
The chemical breakdown of a compound due to reaction with water.
- What are two characteristics of carbon that make it such a valuable element in living organisms?
The two most important characteristics of carbon as a basis for the chemistry of life, are that it has four valence bonds and that the energy required to make or break a bond is just at an appropriate level for building molecules which are not only stable, but also reactive.
- What are the functional groups important in biological systems? Give an example of where these functional groups are found in living organisms.
A functional group is a group of atoms that confers a special property in a carbon molecule.
Functional groups have their atoms bonded in a special orientation and this orientation helps. Functional groups to be directly involved in biological reactions in biological systems.
- Describe condensation and hydrolysis reactions and what are formed as products of these reactions (bigger or smaller compounds).
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Carbohydrates and Lipids
- What is a monosaccharide used for in a living organism? A polysaccharide? Give examples of monosaccharides, disaccharides and polysaccharides. What functional group is found in mono-, di- and polysaccharides?
Monosaccharide is used as an energy source, Disaccharide: starch, glucose, cellulose.
- Draw the basic structure of a glyceride and triglyceride. What is the difference between a saturated and an unsaturated fat? What kind of fats are the best fats to have in your diet? What are the worst? What functional groups are found in glycerides and where?
Triglycerides are formed by combining glycerol with three molecules of fatty acid. Alcohols have a hydroxyl (HO-) group. Organic acids have a carboxyl (-COOH) group.
Saturated fats contain the maximum amount of hydrogen in their fatty acid chains, and are thus more compact. Unsaturated fats naturally bend because they have double bonds. Fat cells cannot store as much unsaturated fat because it is less dense, thus unsaturated fat does not make people as fat.
- What is a steroid? Give examples of steroid molecules. What are the functions of cholesterol? What functional group(s) are found in cholesterol?
It is a class of lipids that have a, central element in their structure, four carbon rings. Cholesterol molecules help stabilize cells from temperature changes. It is an important compent in cell membraces. It helps transfer calcium into the bone. alkane, alkene, aromatic, alcohol
- Describe the structure of a phospholipid. What is biologically significant about this structure? What important cellular structure is made up of phospholipids? What functional groups are found in phospholipids and where?
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Proteins
- Draw the general structure of an amino acid.
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- An amino acid always contains what two functional groups?
Amino group: NH2
Carboxyl group: COOH
- What is the bond between two amino acids called?
Peptide bond.
- What two functional groups come together to form this bond?
The amino group and carboxyl group.
- What is a byproduct of the formation of a peptide bond?
Two hydrogens and an oygen, which form water ????
- A dipeptide consists of two amino acids held together by a peptide bond. A tripeptide consists of three amino acids held together by peptide bonds. A _____________ consists of many amino acids held together by ___________ bonds.
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