Cellular Respiration
Step 3: Electron Transport Chain
NADH/FADH2 + O2 ---> H2O + ATP

endosymbiotic theory

Cell Function: Protein Synthesis 

our microbiome is a community of all microbes that live in our body. 

chemiosmotic phosphorylation
ADP + P -> ATP

and remember.... it's the sequence of amino acids that determines the structure of a protein (why?) which then determines that protein's function.
​different sequence = different structure = different function

substrate level phosphorylation
​ADP + P -> ATP

Gut bacteria produce hundreds of neurochemicals used by our brains to regulate many physiological and mental processes such as learning, memory and mood. Gut bacteria manufacture about 95 percent of the body's supply of serotonin!

 “microbe” is used to describe organisms that are too small to be seen with the naked eye and include bacteria, archaea, fungi, protists, and viruses.

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for tissues, glands and membranes

Protein Synthesis:
Step 1: Transcription 

Cellular Respiration
Step 2: Krebs (TCA) Cycle
2 pyruvate (3C each) ---> 6CO2 + NADH/FADH2 + ATP

fyi...for real!

Bacteria and archaea are single-celled organisms that do not enclose their genetic material in a nucleus.

eukaryote

fyi...for real!

ATP synthase transfers the energy from the concentration gradient of the ETC to a molecule of ATP by bonding P to ADP. 

37 trillion

Viruses are also considered microbes although since they can only reproduce by using another cell’s machinery to make new viruses,
they are not usually considered alive.

100 trillion

mostly GI tract but also skin surface, 
mouth, respiratory tract, reproductive tract, nasal passages, urinary tract, and blood

our microbiome aids digestion, produces vitamins, and supports our immune function. 

The hydrogen from the NADH and FADH2 (originally from the glucose molecule...NADH/FADH2 carry the H from the Kreb cycle to the ETC) is transferred along a series of acceptors via redox reactions. Energy is released as this occurs which pushes H+ across the inner membrane of the mitochondria setting up a concentration gradient. The H+ then moves back across the membrane through the ATP Synthase (think water wheel) which uses the kinetic energy of this movement to bond P to ADP. The last acceptor for the H that has travelled down the chain is oxygen which bonds to H to form water. 

three different sequences = three different structures = three different functions

pathogenic   vs    symbiotic

what about archaea...?

breast milk provides probiotic bacteria to populate the baby’s gut.
it also contains prebiotic complex carbs/proteins babies can't digest but that serve as food for Bifidobacteria, microbes which line the baby's intestines and prevent infection by pathogens. 

current members of Domain Archaea used to be classified as bacteria in Domain Bacteria and at the time were called archaebacteria. however, archaea display a different biochemistry and evolutionary history from bacteria (eubacteria). still, ​both are prokaryotes. 
Archaea can be found in tough environments such as salt lakes (halophiles), swamps and marsh (methanogens) and hot springs (thermophils).

 1/2 million microbe species populate our planet but just a few hundred have evolved to symbiotically live with humans!
Our microbiota is acquired starting at birth from mom's birth canal and breast milk. then dad's kisses. Sister's hand holding. The dog licking fingers. We then encounter microbes in/on the soil and water and plants. We eat microbes with our food. Most microbes do not have the tools to join our microbiome. Others that do must compete with the microbes already established. The process of selection occurs. Microbes identify our cell's surface proteins
to help them find their niche in/on our bodies...chemical communication and physical cues. temperature etc.
Our microbiome is not randomly assembled.
Rather, it is a complex dance of mutual selection. 

fyi...for real!

bacteria vs virus

2/5 lbs
​3 pints

bacteria

our microbiome

Many prokaryotes can perform aerobic cellular respiration by transporting
electrons across their cell membrane. Even though they don't have mitochondria, bacteria can produce ATP energy via glycolysis and by also generating a concentration gradient of H protons across their cell membranes. Structures called mesosomes perform the function of mitochondria in bacteria. Mesosomes 
 increase the surface area of the cell's membrane (analogous to the cristae in the
mitocondria) which increases the area available for respiration. 

where are microbes found in/on our bodies?

Sickle Cell Disease:
A mutation in the gene that codes for the hemoglobin protein causes Sickle Cell  Disease.
This mutation changes one nucleotide in the gene that codes for the hemoglobin protein. 
This one nucleotide change causes a different amino acid to be substituted in the sequence of amino acids in the hemoglobin protein which is enough to completely change the structure of that protein which alters its function. The  resulting protein, made using the code from this mutated gene does not function...all because of ONE nucleotide difference! 

if bacteria don't have mitochondria,
how do they process energy??

prokaryotic bacteria/archae

Protein Synthesis:
Step 2: Translation

the CODE ​ 

So... cellular respiration transfers the energy harvested from the bonds of a glucose molecule to the bonds of ATP molecules.
​whew!

the AMAZING cell!

Eukarya include all the plants and animals you can see and many 
microbes including some fungi some algae, and protists like amoebas.

how does antibiotic resistance happen?

How does a particular tRNA "know" which of the 20 amino acids (shown to the right) to carry?

It's all about the codon of that tRNA. The codon determines which of the20 amino acids that tRNA carries to the ribosome.