Chapter 2 - Chemical Principles

Question 1

Proteins

Answer 1

-organic molecules that contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur
-make up 50%+ of a cells dry weight
-essential aspects of structure and function
-consist of subunits called Amino Acids

Question 2

Enzymes

Answer 2

-proteins that speed up chemical reactions

Question 3

Protein Fucntions

Answer 3

-transport chemical in and out of cells
-kill bacteria
-can be toxins
-contraction of animal muscle cells
-cell movement
-structure of cell walls, membranes, cytoplasmic components
-can have regulatory functions such as hormones

Question 4

Amino Acids

Answer 4

-the building blocks of proteins
-contain at least one carboxyl group and one amino group attached to the same carbon atom
-a side group also attaches, this is the amino acids distinguishing feature

Question 5

Carboxyl Group

Answer 5

-COOH
-a central C double bonded to an O and a single bonded OH

Question 6

Amino Group

Answer 6

-NH₂
-a N single bonded to the central C with 2 Hydrogens single bonded separately

Question 7

Side (R) Group

Answer 7

-distinguishing feature
-can be H, CH2, an organic molecule
-affect the total structure of the protein

Question 8

Dehydration Synthesis

Answer 8

-anabolic, requires ATP
-removes a water group to bind amino acids together

Question 9

Peptide Bonds

Answer 9

-formed by dehydration synthesis
-bind Amino Acids together on opposite sides to create a polypeptide chain
-for every bond, one water molecule is releases

Question 10

How many Amino Acids make up 1 protein molecule?

Answer 10

about 250-300

Question 11

Primary Structure

Answer 11

-the Amino Acids are linked together to form a polypeptide chain
-a genetically determined sequence

Question 12

Secondary Structure

Answer 12

-repeated twisting or folding of the polypeptide chain
-results from hydrogen bonds joining the peptide bond atoms at various locations
-can form as helices/helix or pleated sheets

Question 13

Tertiary Structure

Answer 13

-3D structure of a polypeptide chain
-folding is not repetitive/predictable
-not held together by hydrogen bonds, instead by action in the side groups (polar molecules)

Question 14

Quaternary Structure

Answer 14

-gathering of 2+ polypeptide chains to operate as a single functional unit
-same bonds as tertiary
-may be globular or fibrous

Question 15

Denaturation

Answer 15

-hostile environment (ie. temp, pH, Na+ conc.) may unravel the protein
-this makes the protein no longer functional

Question 16

Nucleic Acids

Answer 16

-consist of nucleotides
-DNA and RNA

Question 17

Nucleotides

Answer 17

-have a pentose sugar, phosphate group, and a nitrogen base

Question 18

Nitrogen Base

Answer 18

-can be purine or pyrimidine
-cyclic compounds made uo of carbon, hydrogen, oxygen, and nitrogen
-GCATU
-create the rungs of the ladder

Question 19

Purine Base

Answer 19

-double ring structures
-adenine (A)
-guanine (G)

Question 20

Pyrimidine Base

Answer 20

-single ring structure
-thymine (T)
-cytosine (C)
-uracil (U)

Question 21

Nucleoside

Answer 21

combination of a purine/pyrimidine + a pentose sugar without a phosphate group

Question 22

Hydrogen Bonds

Answer 22

-hold together the rungs on the ladder (nitrogen bases)
-shown as broken lines yes are rather stable

Question 23

G + C

Answer 23

-guanine and cytosine held together by a triple hydrogen bond

Question 24

A + T

Answer 24

-adenine and tyrosine held together by a double hydrogen bond

Question 25

Pentose Sugar Group

Answer 25

-a 5 carbon atom in the shape of a pentagon with one oxygen
-carbons are numbered 1-5 starting after the oxygen group and moving clockwise
-with phosphate creates the backbone
-there is an OH group bound to C2 and this extra O creates ribose sugar
-each C is hyphenated to differ from Cs not apart of the sugar

Question 26

Phosphate Group

Answer 26

-often starts as PO4- which is unbalanced
-phosphate becomes balance when it makes DNA
-creates backbone of the ladder

Question 27

DNA

Answer 27

-2ʹ-deoxyribonucleic acid
-the master molecule of the cell
-GCAT
-double helix form/twisted ladder

Question 28

RNA

Answer 28

-ribonucleic acid
-the workbench for protein synthesis
-sugar is full ribose, not deoxygenated
-single stranded rather than double helix
-has uracil: GCAU

Question 29

Types of RNA

Answer 29

1) mRNA: messenger RNA
2) rRNA: ribosomal RNA
3) tRNA: transfer RNA
-all have roles in protein synthesis

Question 30

What makes deoxyribose?

Answer 30

-ribose has a OH group at C2
-deoxyribose has only a H at C2

Question 31

ATP

Answer 31

-adenosine triphosphate
-principle energy carrying molecule of the cell
-stores energy released by some chemical reactions
-consists of an adenosine unit (adenine and ribose) and three phosphate groups