Ch 2

Question 1

Aseptic technique

Answer 1

Set of practices and procedures used to prevent contamination from pathogen. Is used when transferring bacteria from one place to another without contaminating ourselves or environment

Question 2

Spectrophotometer

Answer 2

Measures the amount of light transmitted or absorbed directly through a sample OR it measures the turbidity of a sample to estimate cell number

Question 3

Turbidity

Answer 3

Cloudiness

Question 4

Properties of water

Answer 4

65% of our bodies are water
Polar molecules (dipole)
Excellent solvent
Hydrogen bonding
Water acts as a temperature buffer
Can act as a base or acid in chemical reactions

Question 5

Water as a polar molecule

Answer 5

Polar nature makes water an excellent solvent.
Dissolves polar and charged molecules
These compounds are hydrophilic
Water with dissolved substances freeze at a lower temperature

Question 6

Cohesion

Answer 6

Due to polar nature water molecules stick to other water molecules

Question 7

Adhesion

Answer 7

Water molecules stick to other materials due to its polar nature

Question 8

Surface tension

Answer 8

Creates the skin-like surface formed due to the polar nature of water

Question 9

Ph

Answer 9

The concentration of H+ in a solution

Question 10

Acid

Answer 10

Releases H+ . Proton (H+) donor

Question 11

Base

Answer 11

Releases OH- proton (H+) acceptor

Question 12

Acidic scale

Answer 12

0 = most acidic. 14= most basic. 7 = neutral

Question 13

Ph of aqueous solutions

Answer 13

Pure water has equal concentrations of each so its neutral
Each log unit represents ten-fold change in [H+]
Buffer stabilizes (keep in defined range) ph of solution
Most cells like to grow in neutral ph

Question 14

4 major classes of organic molecules

Answer 14

Carbohydrates: monomer of monosaccharide
Lipid: monomer are fatty acids
& glycerol
Proteins: monomers are amino acids
Nucleic acids: monomers are nucloticles

Question 15

What is a monomer?

Answer 15

Individual subunit that make up polymers or macromoteches

Question 16

Carbohydrates

Answer 16

Diverse group includes sugars & starches
Energy source, energy storage
Carbon source
Component of DNA RNA
Structural component of cell

Question 17

Lipids

Answer 17

Lipids are non polar, hydrophobic molecules, made of heterogenous group of compounds, mainly composed of hydrocarbon chains
Energy storage (for long use)
Cell membrane
Hormones

Question 18

Lipid monomer

Answer 18

Fatty acids & glycerol
Bacteria in our gut makes short chain fatty acid chains that feed intestinal wall cells

Question 19

Phospholipids

Answer 19

Very important part of cell membrane
Protects the cell from the outside environment. Selective permeability

Question 20

Structure of phospholipids

Answer 20

Phosphate group linked to polar molecule hydrophilic head, Hydrophobic fatty acid tails. Form lipid belayer
Essential component of cytoplasmic membrane

Question 21

Triglycerides

Answer 21

Common fats found in our body
Glycerol linked to fatty acids via dehydration synthesis
Fatty acids are chains of bonded C,H atoms with carboxyl group at one end

Question 22

Saturated fats vs unsaturated fats vs trans fats

Answer 22

Sat. No double bonds
Unsaturated- trans: h atoms opposite
(hard to break down)
Unsaturated-cis: bent ( naturally occurring)

Question 23

Proteins

Answer 23

Most common organic molecule
Composed of amino acids

Question 24

Function of proteins

Answer 24

Enzyme are catalyst
Transport
Provide mechanical support
Generate mechanical support
Generate movement/motility
Cell receptors
Regulation of gene expressions

Question 25

Amino acids

Answer 25

20 amino acids, protein characteristics depend mainly on shape(determined by amino acid sequence )

Question 26

Amino acid structure

Answer 26

Central carbon, carboxyl group, amino group, side r-group

Question 27

Peptic bonds

Answer 27

Hold amino acids together
Covalent bonds formed by reaction between carboxyl + amino
Dehydration synthesis

Question 28

Protein structure

Answer 28

Proteins are one or more long polypeptide folded to create functions modules

Question 29

Protein structure levels

Answer 29

Primary: sequence of amino acids
Secondary: hydrogen bonds & beta sheets chain folding
Tertiary: 3D shape of protein
Quaternary: 2 or more polypepticle

Question 30

Folded proteins vs denatured protein

Answer 30

Fp: Specific function & domains
Dp: loss of function no domain

Question 31

How proteins denature

Answer 31

High temperature, extreme ph, solvents an break bonds

Question 32

DNA vs RNA

Answer 32

D: genetic information found in cell or genes, double stranded,deoxyribose,ATGC, strands are antiparallel ( 5’ to 3’) strands are complementary

R: RNA is made from DNA, single stranded, RNA synthesizes proteins, many types ( mRNA, tRNA, tRNA ) ribose,AUCG

Question 33

DNA is eukaryotes vs prokaryotes

Answer 33

Eukaryotes: found in nucleus 46 chromosomes
Prokaryotes: found in cytoplasm of cell in region called nucleoid 1 circular chromosome

Question 34

mRNA, tRNA, tRNA

Answer 34

Messenger RNA carries DNA to ribosomes
Transfer RNA transfers amino acids to ribosomes
Ribosomal RNA makes up ribosome - protein factories of the cell

Question 35

The role of ATP

Answer 35

Adenosine triphosphate
ATP → adp+pi
3 negatively charged phosphate groups repel
Bonds unstable easily broken
Releases energy to drive cellular process
High energy phosphate bonds denoted by -