Lecture 6 Cell Physiology Flashcards
Cells can perform chemical processes in the body like metabolism, two components of metabolism are
Anabolism (build molecules)
Catabolism (break)
Smallest living unit
Cell
Example of proteins are
Enzymes Structural molecules Signalling molecules Transporters (Actin myosin and some hormones)
What is DNA transcription
When DNA template used to make mRNA
How does transcription make mRNA
DNA uncoils - exposes base sequence
RNA formed using the code on DNA template and adds complementary nucleotides
If the DNA strand is 3’ to 5’ and contains the code
ATCGCA
What would the RNA strand be
5’ UAGCGU 3’
DNA is always _’ to _’
3 to 5
What is translation ?
The use of the mRNA to form proteins
mRNA associates with ribosomes during translation, explain how this happens
3 bases on RNA are codons (which code for AA)
The mRNA seeks out ribosomes and stuffs it’s cute little self inside
Then a tRNA will come along with it’s anticodon that is complementary to the mRNA codon WITH it’s associated AA
This happens over and over- peptide bonds form
mRNA is always _’ to _’
And each 3 base codes is a ___
Each codon codes for one amino acid BUT there may be________
5’ to 3’
Codon
More than one code for an amino acid
Eg: aUG and UAG May code for the same AA (exampaline) but UAG could never code for a differentexampaline
If the protein was synthesized by the cytoplasmic ribosomes it will either be….
Released to cytosol
Travel to nucleus or
Travel to mitochondria
If the protein is synthesized by the RER
Protein will be released into the lumen of the ER and modified
What kinds of modifications happen to a protein in the ER
Sugars added : glycoproteins
After the protein has been modified by the ER where does it go and what happens
Golgi bodies
CHO changes and additions take place
Used as tags to ensure protein goes to it’s destination
Lipids are added here
After Golgi bodies where do the newly modified proteins go and how
Modified proteins packaged into vesicles and sent to Cell membrane Or Secretion from the cell Or Lysosomes
Let’s talk about lysosomes
Membrane bound organelles containing digestive enzymes
Present in acidic environment
Maybe the enzymes came from Golgi proteins ??? ;)
Enzyme function
Speed up chemical reaction
Example of an enzyme in action
Carbon dioxide and water (substrates) Enzyme - carbonic anmhydrase React to produce Carbonic Acid H2CO2 The reaction occasionally will progress in both directions catalyzed by the same enzyme
ATP is composed of
Adenine
Ribose
3 phosphates
Adenine and ribose = adenosine
Where is the NRG stored in the ATP
In the bonds between the phosphate groups A-P~P~P -----> A-P~P / Pi / E Adenosine di-phosphate Inorganic phosphate NRG
What can ATP be used for ?
Active transport
Protein synthesis
Muscle contraction
Cellular respiration is the pathway for
ATP production
Cellular respiration is powered by the breakdown of
Glucose molecules
How is glucose taken into a cell
Facilitated diffusion
- insulin
Glucose within a cell is higher following ______ secretion
Insulin
Cellular respiration has 3 stages and they’re so boring what are they
Glycolysis
Kerbs cycle
Electron transport chain
Tell me about glycolysis
Where it occurs
Oxygen?
Produces ?
In cytosol Doesn't need 02 2 NADH 2 ATP 2 pyruvate
In glycolysis there are 6c initially which now has turned into 2 ____
If there is no oxygen these products will go on to form 2 ____.
Pyruvate
Lactic acid
If there is oxygen the 2 pyruvate 3C may enter into intermediate step before Krebs cycle .. What happens there?
2 pyruvate turn into 2 actyl coA (2C) And since a carbon was knocked off from each pyruvate 2 carbon dioxide 2 NADH
In Krebs cycle the 2 actyl coA are completely metabolized to
4 CO2
Krebs cycle also produces
2 ATP
6 NADH
2FADH
The conversion of a glucose to 2 pyruvate during glycolysis makes use of ____ enzymes
10 enzymes
How many NADH arrive at the electron transport chain ?
10
2- glycolysis
2- intermediate
6- Krebs
In the electron transport chain the electrons from the NADH are passed from electron carrier to electron carrier and releases NRG to form ATP. How much ATP in total is produced
38 max
How much oxygen and water used for electron transport
6 molecular oxygen
12 water molecules
1 glucose / 6 C reacts to produce \_\_\_\_\_ CO2 \_\_\_\_\_ H20 \_\_\_\_\_ ATP And heat
6
6
36 - 38
T or F amino acids can be made from proteins and some AA can be converted into pyruvate which can enter into Krebs
T
Fats are the primary source of NRG used in the body (triglycerides) they can be broken down into _____ to make ATP
Acetyl coA
