Intro Cell Biology

Question 1

The Big Picture of Cell Biology

Answer 1

Regulation of gene expression and metabolism in cells determine physiology.

Question 2

Synthesis

Answer 2

-cellular respiration
-glucose to pyruvate produces 2 NADH and 2 ATP
-Pyruvate to 2 Acetyl CoA produces 2 NADH and 2 CO2
-2 Acetyl CoA to the Krebs cycle produces 6 NADH, 2 FADH2, 4 CO2 and 2 ATP
-The NADH and FADH2 leave there H+ in the electron transport chain where O2 attaches and become water.
-34 ATP are created in cellular respiration.

Question 3

Proteins: Transcription and Translation

Answer 3

-DNA (genotype) is transcribed
-mRNA is translated by ribosomes
-polypeptide protein to phenotype, cellular functions carried out by proteins, such as enzymes.
-Making mRNA and protein takes ATP.

Question 4

Transcription: Promoter and Terminator

Answer 4

-Promoter (TATA) then
-Gene which RNA transcripts over with a RNA polymerase at the end of the RNA
-Terminator stops transcription

Question 5

Enhancer + Activator Protein

Answer 5

-Activators recognize enhancers and bind to them increasing transcription.
-Enhancer works with the architectural (DNA bending) protein

Question 6

Silencer + Repressor Protein

Answer 6

-Repressor is in place of a architectural (DNA bending) protein and is a different shape.
-The silencer and repressor work together.

Question 7

What is added to the ends of a mRNA strand?

Answer 7

Caps and tails

Question 8

What are exons and introns?

Answer 8

-Exons are the pieces of the DNA that get translated.
-Introns are the DNA that gets spliced out.

Question 9

Ribosomes

Answer 9

Ribosomes have a large and a small subunit.

Question 10

Post-Translational Modifications

Answer 10

-Occur on Protein!
-regulates protein compartmentalization/trafficking and activity
-protein gets translated at the ribosome.

Question 11

Post-Translation Modification protein products (PUGS)

Answer 11

-Phosphorylation = protein + phosphate
-Glycosylation = protein + carbohydrate
-Ubiquitylation = protein + ubiquitin
-SUMOylating = protein + SUMO/Ubc9

Question 12

Summary of Gene Expression

Answer 12

1. Alteration in chromatin structure
2. Initiation of transcription
3. Transcript elongation
4. Termination of transcription
5. RNA processing
   a) Capping
   b) Cleavage
   c) Polyadenylation
   d) Splicing
6. Nucleocytoplasmic
7. Tanslation
8. mRNA degradation

Question 13

Secretory Pathway

Answer 13

-signal sequence is like a zip code and if a protein has one it goes through the secretory pathway
-Proteins that will be secreted outside the ER through a translocon
-Hormones are made and put in the blood
-hormones are made by gene expression and the secretory pathway

Question 14

Secretory Pathway Steps

Answer 14

1. ribosomes are on Rough ER
   2.Protein go through the rough ER and then into carrier vesicles that transport them to the Golgi
2. The Golgi has three parts the cis, medial, and trans. The protein go through a further process of being modified when here.
3. The vesicles then take the protein and release it through the cell membrane through constitutive or regulated pathway

Question 15

Regulated pathway

Answer 15

-release from a response
-secretion is directed by hormonal or neural signal

Question 16

Constitutive Pathway

Answer 16

-secretion is continuous and unregulated

Question 17

Recap: Secretory Pathway

Answer 17

Peptide hormone example
-Nucleus-mRNA (transcription)
-Cytosol-mRNA/ribosome and start of translation
-ER-translation continues with translocon entry and packing of protein into vesicles
-Golgi-movement to and through Golgi network and protein is processed into peptide hormone
-Vesicle then trafficked to membrane for release from cell into blood

Question 18

Golgi

Answer 18

further process occurs, cut up, protein modified