ch 9,10, & 12

how do cells oxidize glucose?

a long series of controlled redox reactions; energy is produced to make ATP

4 processes of cellular respiration

1. glycolysis
2. pyruvate processing
3. citric acid cycle
4. electron transport chain

glycolysis

converts 6-carbon glucose into two 3-carbon pyruvate

pyruvate processing

converts 3-carbon pyruvate into acetyl CoA

Citric acid cycle

fully oxidizes the remaining carbons in acetyl CoA to CO2

electron transport chain

oxidative phosphorylation to make ATP

where does glycolysis take place?

Cytosol of eukaryotes and prokaryotes

what goes in glycolysis?

glucose + 2 ATP

What goes out in glycolysis?

2 ATP + 2 NADH + 2 Pyruvate per glucose

how is glycolysis regulated?

feedback inhibition

\

what is produced in glycolysis?

ATP

Aerobic respiration

* oxygen in the final electron acceptor
* in all eukaryotes and prokaryotes
* most efficient (electronegativity)

anaerobic respiration

* a molecule other than oxygen is the final electron acceptor
* some prokaryotes

what happens when there is no electron acceptor?

fermentation

what is an alternative to Cellular respiration?

fermentation

cellular respiration

any set of reactions that uses electrons harvested from high energy molecules to produce ATP via an electron transport chain

photosynthesis

the use of sunlight to manufacture carbohydrates

what are the 2 reactions of photosynthesis?

light-dependent and light-independent

where does photosynthesis occur?

chloroplast

what is the most common pigment?

chlorophyll (specifically A)

thylakoid

flattened sacs

granum

stack of thylakoids

stroma

space surrounding thylakoids

lumen

space inside thylakoid

blue light

shorter, high energy

red light

lower energy

where do chlorophyll molecules work together?

in photosystems

what are photosystems compromised of?

1. antenna complex
2. reaction center
3. proteins

antenna complex

* light-harvesting complex
* 200-300 pigments

reaction center

special pair of chlorophyll A molecules

proteins

aid in energy capture/processing of electrons

what happens to energy in the antenna complex?

energy is absorbed and passed through resonance energy transfer

what does photosystem II do?

makes ATP

What are the steps of PSI?

1. absorption of light; with antenna complex
2. reaction center gives e- to an electron acceptor; 2 electrons are excited in reaction center chlorophyll molecules
3. ferredoxin = electron acceptor
4. NADP+ transfers 2 electrons and proton to reduce NADP+ and form NADPH

how does PS I and II interact?

Z-scheme

what does PS I create?

NADH

what are the 3 phases of the carbon cycle?

1. fixation
2. reduction
3. regeneration

what is the enzyme that catalyzes the first reaction in the CC?

Rubisco - ribulose, 1,5 biphosphate carboxylase/oxygenase

how is photosynthesis regulated?

* light triggers production of proteins and activates rubisco
* high sugar inhibits and triggers proteins involved in storage
* low CO2 inhibits rubisco

what are the 2 strategies to prevent water loss?

C4 Photosynthesis and CAM photosynthesis

steps of cellular replication

1. copying the DNA
2. separating the copies
3. diving the cytoplasm to create 2 complete cells

chromosome

a single long double helix of DNA wrapped around proteins called histones

chromatin

makes up a chromosome

what does DNA do?

encode the cells genetic info

gene

a section of DNA

Chromatid

double-stranded DNA copy of a replicated cell

centromere

region of attachment for sister chromatids

4 phases of mitosis

1. G1 (first gap)
2. s phase (DNA synthesis)
3. G2 (2nd gap)
4. Mitosis

Interphase

* chromosomes replicate
* chromatin is relaxed

M phase: mitosis

* starts when chromatin condenses
* 2 sister chromatids separate
* 1 copy of each chromosome goes to each daughter cell
* 5 subphrases (prophase, prometaphase, metaphase, anaphase, and telophase)

\# of chromosome and DNA molecules in Prophase

4, 8

\# of chromosome and DNA molecules in pro metaphase

4, 8

\# of chromosome and DNA molecules in metaphase

4, 8

\# of chromosome and DNA molecules in anaphase

8, 8

\# of chromosome and DNA molecules in telephone

8, 8

difference between plant and animal cell cytokinesis

plants - occurs when a cell wall forms

animals - occurs when a cleavage furrow forms, pinches cell in half

rapidly dividing cells

G1 essentially eliminated

non-dividing cells

permanently stuck in G1

George washington carver

* Agriculture scientist and inventor - focused on peanuts
* Promoted techniques for soil heal and alternative crops
* Born into slavery, raised by enslaved when slavery ended
* 1st black student of Iowa State AC
* First black faculty member at Iowa and Tuskegee

How long can ATP sustain in the cell?

30 seconds to a few minutes

Cellular Respiration

Glucose + O2 → CO2 + H2O + Energy

C is oxidized and O is reduced

CR vs fermentation

* cr produces more energy
* fully oxidized glucose vs partially oxidized glucose

ATP is made through

substrate-level phosphorylation

what is the 3rd enzyme in glycolysis?

phosphofructokinase

how is glycolysis regulated?

feedback inhibition; ATP inhibits the 3rd enzyme

* there are 2 binding sites for ATP

fermentation

* results in ATP production and the production of Pyruvate by-products
* way of dealing with NADH buildup
* regenerates NAD+
* emergency “back up”

alcohol fermentation occurs in

yeast

lactic acid fermentation occurs in

humans

what happens when cells receive oxygen?

lactic acid returns to pyruvate

how much ATP is produced by fermentation?

2 ATP per glucose

how many ATP is produced by CR?

29 ATP per glucose

organisms that can switch back and forth between fermentation and aerobic are called?

facilitative anaerobes

how is pyruvate processed?

pyruvate dehydrogenase

location of pyruvate processing in prokaryotes?

cytosol

location of pyruvate processing in eukaryotes?

mitochondrial matrix

what is pyruvate processing regulated by?

feedback inhibition

* inhibited when phosphorylated (lots of products)

PP per glucose

2NADH → ETC
2 CO2 → Exhaled
2 acetyl CoA → CAC

location of CAC in eukaryotes

mitochondrial matrix

location of CAC in prokaryotes

cytosol

Glycolysis net yield

2 NADH, 2 ATP, 2 Pyruvate

pyruvate processing net yield

1 NADH, 1 CO2, and 1 acetyl CoA for each pyruvate molecule

cac net yield

3 NADH, 1 FADH2, 2CO2, and 1 ATP for each acetyl CoA molecule

when are the rates of CAC low?

when NADH or ATP is abundant

how many turns foes each can take per glucose?

2 turns

yields: 6NADH, 2 FADH2, 2ATP, 4 CO2

products from glycolysis through cac

6CO2 - exhaled

4ATP - used directly as fuel

10 NADH →ETC

2FADH2 → ETC

what occurs in the ETC?

NADH and Fadh2 are oxidized to form water

ETC organization?

4 protein complexes

what do Q and cytochrome C transfer?

electrons between the complexes

etc location in eukaryotes

inner membrane of mitochondria

etc location in prokaryotes?

plasma membrane

energy used to pump protons forms?

electrochemical gradient

ATP synthase

* discovered by Recker and colleagues in 1960
* 25 ATP produced per glucose molecule

what is ATP synthase?

Enzyme that uses electrochemical gradient created by ETC to generate ATP = chemiosmosis

* movement of ions down electrochemical gradient

edmond alibis

* Horticulturalist
* Born into slavery in Reunion
* Began cultivating vanilla at age 12
* revolutionized vanilla cultivation through pollinating stats
* technique falsely claimed by French botanist Jean Richard
* died in poverty after outlaw of slavery

what does photosynthesis covert electromagnetic energy to?

chemical energy

photosynthesis equation

CO2 + H2O + Light Energy → (CH2O)n + O2

light-dependent reactions

photosynthesis occurs in the chloroplasts; most have 2 membranes (brown algae has 4)

what powers photosynthesis?

absorption of light (photons) by pigments

* each pigment absorbs unique wavelengths

pigments appear to human as the color

they do NOT absorb

visible light spectrum

* violet/purple have the highest light energy
* red has the lowest light energy