Exam 3

Question 1

Carbohydrates

Answer 1

polyhydroxyl ketones or polyhydroxyl aldehydes and their derivatives

Question 2

Biological membrane

Answer 2

lipid bilayer containing protein which completely surrounds and isolates biomolecules

Question 3

ionophores

Answer 3

a biomolecule which facilitates the movement of ions across a biological membrane

Question 4

lipid

Answer 4

biomolecules which are insoluble or slightly soluble in water and usually extractable by organic (non polar) solvents.

Question 5

cascade

Answer 5

a series of biochemical reactions which amplify so that the number of final products is orders of magnitude greater than the number of initiating molecules.

Question 6

effector enzymes

Answer 6

an enzyme component of a signal transaction pathway which is bound to a membrane, activated by transducer, and produces a second message.

Question 7

receptor

Answer 7

a transmembrane protein component of a signal transduction pathway to which an external signal molecule will bind to cause conformational change and subsequently activate a transducer molecule.

Question 8

second messenger

Answer 8

a molecule which is part of a signal transduction pathway and which is produced as a consequence of the binding of the extracellular signal.

Question 9

signal transduction

Answer 9

usually combined with the word signal to refer to the transfer of information from one side of a membrane to another.

Question 10

nucleic acids

Answer 10

biopolymers consisting of nitrogenous bases which are linked to ribose or deoxyribose linked by phosphodiester bonds.

Question 11

mRNA

Answer 11

is a class of RNA molecules which carries a copy of the sequence of nucleic acid bases from the DNA to the ribosomes where these sequences are translated into a series of linked amino acids to form proteins

Question 12

tRNA

Answer 12

a series of RNA molecules composed of 75-95 nucleotides which are charged with an amino acid by the appropriate tRNA synthetase enzyme and which carry that activated amino acid to the ribosome

Question 13

rRNA

Answer 13

this series of RNAs combine with proteins to form ribosomes

Question 14

nucleoside

Answer 14

are composed of ribose or deoxy ribose and a heterocyclic base

Question 15

nucleotide

Answer 15

are phosphorylated derivates of a nucleoside

Question 16

enthalpy

Answer 16

delta (h) = the measure of the amount of heat generated under constant pressure

Question 17

entropy

Answer 17

delta (s) = the measure of the disorder of a system

Question 18

Gibb’s Free Energy

Answer 18

is the amount of energy available to do chemical work

Question 19

snRNA

Answer 19

small nuclear ribonucleic acid - this is a series of RNA molecules ranging in size from about 100-300 nucleotides long.

Some combine with proteins to form complexes, splicesomes, which remove introns from eukaryotic mRNA

Question 20

annealing

Answer 20

as the process by which two strands of complementary nucleic acid bases bind to each other.

It is measured by the rate at which this occurs as it is a kinetic process. The rate is dependent upon the concentration of strands solution, the length of these strands, and the uniqueness of the sequences.

Question 21

palindrome

Answer 21

is a sequence of letters which read the same in one direction as in another.

For nucleic acid sequences, this refers to the sequence of bases of one strand as read from 5’ to 3’ as compared with the complementary strand as read from 5’ to 3’. For example, the sequence GGATCC is palindromic. Restriction enzymes typically recognize palindromic sequences.

Question 22

restriction enzymes

Answer 22

protein endonucleases which cleave at a specific DNA sequence, which is typically a palindrome.

Question 23

snRNA

Answer 23

small nuclear ribonucleic acid - this is a series of RNA molecules ranging in size from about 100 to 300 nucleotides long.

Some combine with proteins to form complexes, splicesomes, which remove introns from eukaryotic mRNA

Question 24

Tm

Answer 24

the temperature at which a particular molecular transition is 50% completed.

Question 25

transducer

Answer 25

a protein component of a signal transduction pathway which is activated by a receptor and in turn alters the activity of an effector enzyme.

Question 26

endonuclease

Answer 26

a nuclease which cleaves an internal phosphodiester bond.

Question 27

exonuclease

Answer 27

a nuclease which removes one nucleotide from one end of a nucleic acid.

Question 28

melting

Answer 28

the process by which two strands of complementary nucleic acid bases separate from each other.