Lecture 1 - Intro

Question 1

What is hydrophilic?

Answer 1

water loving
polar molecules (salt, ions) will solve

Question 2

What is hydrophobic?

Answer 2

water fearing
non-polar molecules (fat, oil) will not solve

Question 3

What are amphipathic molecules?

Answer 3

have regions that are polar (hydrophilic) and nonpolar (hydrophobic)

Question 4

What is the chemical definition of acid (Bronsted-Lowry)?

Answer 4

proton (H+) donors
biologically important: weak acids (carbonic acids, citric acid)

Question 5

What is the chemical definition of base (Bronsted-Lowry)?

Answer 5

proton (H+) acceptors
biologically improtant: weak bases (ammonia)

Question 6

What is the pH of pure water?

Answer 6

7 (calculation at 25 degrees celsius)

Question 7

What are buffers?

Answer 7

mixture of weak acids + conj strong base
weak base + conj strong acid

Question 8

What is the function of buffers?

Answer 8

maintain normal pH of biological systems
neutralize small quantities of additional acid or base

Question 9

What is buffer capacity?

Answer 9

amoutn of acid or base that can be added to buffer before chaning its pH

Question 10

What is an example of buffers in human body?

Answer 10

blood: bicarbonate buffer system to keep blood pH between 7.35-7.45
eliminates CO2

Question 11

What is acidosis?

Answer 11

if blood pH is lower than normal

Question 12

What is alkalosis?

Answer 12

if blood pH is higher than normal

Question 13

What is the Henderson-Hasselbalch equation used for?

Answer 13

calculate pH of buffered solution

Question 14

Which of the 4 major biomolecule types contains carbon?

Answer 14

all of them: proteins, carbohydrates, lipids, nucleic acids

Question 15

What is the main feature of a covalent bond with regard to electrons of 2 molecules?

Answer 15

share electrons
polar covalent bond: electronegative molecule will take majority of electrons

Question 16

Difference between intramolecular and intermolecular?

Answer 16

intramolecular: within molecule (STRONGER)
intermolecular: between molecules

Question 17

What is a hydrogen bond?

Answer 17

H and electronegative atom (FON)
how bases in DNA are bonded

Question 18

What are functional groups?

Answer 18

groups of atoms that contribute to the chemical characteristics of the molecule
participate in predictable reactions
characteristic groups in organic molecules that give them their reactivity
examples: ester, amide, amine, nitrate, alcohol, aldehyde, ketone, carboxylic acid