CSUN BIOL 107 Lab Exam 1 (Labs 1-4)

Proteins

chains of amino acids
linked together by peptide bonds

Monomers

individual molecules

Polymers

multiple monomers
combined together

Amino acids

building blocks for proteins

What do proteins do?

enzymes, hormones, structural support, defense, movement, transport

Bradford assay

detects proteins in the sample by binding to the
amino acids. If the protein is present, it turns blue. If not, it turns brownish-green

What does a spectrophotometer measure?

it measures [molecule] in a sample by using light
• higher [protein] = high absorbency, less light passing through
• lower [protein] = lower absorbency, more light passing through

also measures ABSORBANCE or TRANSMITTANCE

What do fish use their gills to extract from water?

dissolved oxygen (DO)

Where do Soda/carbonated drinks
get their fizz from?

dissolved CO2

How soluble a gas is in liquid depends on factors like what?

temperature and pressure

Gasses are more soluble
(dissolve better) in _____ liquids / water?

cold

Increased pressure causes an

increase in dissolved O2

A decrease in pressure may

cause the O2 to leave a solution

Acidic

less than 7 on the pH scale, H+ ion

Alkali

greater than 7 on the pH scale, OH- ion

Aerobic

an organism using oxygen

Anaerobic

an organism not using oxygen

Obligate
aerobe

an organism that cannot survive without
oxygen

Obligate
anaerobe

an organism that cannot survive
with oxygen

Facultative
anaerobe

an organism that can live with or
without oxygen

Cellular respiration

the metabolic reactions that break
down molecules (such as glucose) and release energy
▪ Occurs in almost all organisms (animals, plants, bacteria,
etc.) because living things require energy!

Adenosine Triphosphate (ATP)

 a molecule composed of
adenine, ribose, and three
phosphate groups
 High-Energy Bonds: Stores
energy in phosphate bonds
 Energy Carrier: Powers cell
functions

What are the steps of cellular respiration?

▪ Three steps:
1. Glycolysis (occurs in cytoplasm of cells)
2. Krebs Cycle/Citric Acid Cycle (occurs in the
mitochondria)
3. Electron Transport Chain (occurs in the
mitochondria)

Glycolysis

▪ Occurs in the cytoplasm of the cell
▪ No oxygen required! (anaerobic)
▪ To begin the process, 2 ATP molecules
need to be invested
▪ 6-carbon glucose is split into two
smaller 3-carbon pyruvate molecules
▪ ATP and NADH molecules are
produced

Kreb’s Cycle/Citric Acid Cycle

▪ Occurs in the
mitochondria of cells
▪ Pyruvate gets converted
to Acetyl-CoA
▪ Oxygen IS required!
(aerobic)
▪ Series of reactions that
produce ATP, NADH,
FADH2 and CO2

Electron Transport Chain

▪ Occurs in the
mitochondria of cells
▪ Oxygen acts as the
final electron
acceptor that “pulls”
electrons from
NADH + FADH2
down the electron
transport chain
▪ Produces 90% of the
ATP in your body!

Glycolysis
+
Kreb’s Cycle
+
Electron Transport Chain

=
36 ATP molecules produced
during cellular respiration!

How many mitochondria are in each cell?

up to 600,000

Chemical equation of photosynthesis

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

_{Carbon dioxide + Water —> Sugar + Oxygen}

Chemical equation of cellular respiration

C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O + ATP
Glucose + Oxygen —> Carbon dioxide + Water + Energy

plants

known as “autotrophs”

□ produce their own food by
converting inorganic sources of
carbon into organic sources of
carbon
(i.e. CO2 → glucose)

▪ “auto” = self
▪ “troph” = food/nourishment

Photosynthesis takes place in

Chloroplasts

What are chloroplasts?

organelles found
in plant & algae cells

▪ The thylakoid membranes of
chloroplasts contain a green
pigment called chlorophyll that is
can absorb photons of light at
specific wavelengths for energy

Light-dependent
reactions take
place in the ___

These reactions
convert light
energy to chemical
energy

thylakoids

ATP + NADPH are
produced to be
used in

the Calvin
Cycle

Calvin Cycle takes
place in the

stroma

What does the Calvin Cycle use to produce sugars?

ATP, NADPH,
and CO2

Sugars produced from the Calvin Cycle
are used to fuel _____ and produce
compounds like
cellulose & starch

cellular respiration

cyanobacteria: Synechocystis

▪ combined features of chloroplasts & mitochondria
– both generate & consume O2
▪ depending on the amount of light exposure, will
cause a net increase or decrease in DO

What do plants conduct?

cellular respiration & photosynthesis