Lectures 6-10 Flashcards
What are teratomas?
tumours developing from pluripotent stem cells containing many different cell types
What is haemopoiesis?
Blood differentiation
What do erythrocytes and platelets stem from?
erythro-megakaryotic progenitors, which come from the common myeloid progenitor
What do B and T cells stem from?
Common lymphoid progenitors
What are the domains of TF’s?
DNA binding domain activation domain (interacts with RNA Polymerase)
What cycle regulates RBC abundancy?
How does is work?
The erythropoietin cycle
Epo stimulates stem cells in the bone marrow to form RBC progenitors,.
This increases the O2 in carrying capacity, having a negative feedback effect on Epo.
This decreased O2 in the proximal convoluted tubule, increasing Epo production.
TCA: what happens to carbon atoms?
They are ‘burned’, being oxidised and released as CO2
The energy released is captured by energy carriers (like NADH), transporting it to oxidative phosphorylation
TCA: What kind of molecule is succinate?
symmetriclal
TCA: What happens to carbon atoms added by Acetyl CoA?
They are added to oxoaloacetate, and are then lost in subsequent cycles
TCA: What are the products of TCA?
CoA + 2CO2 3NADH FADH2 GTP REMEMBER THIS HAPPENS TWICE PER GLUCOSE MOLECULE
ETC: complexes are there?
4 membrane bound ones, 2 mobile electron carriers
ETC: What do NADH and FADH2 do?
transfer high energy electrons to the ECT
ETC: what happens to the electrons?
They progressively decrease in energy level, and are added to )2, and then with H+ to form H20
ETC: What does the energy released do?
drives protons over the inner membrane into the inter-membrane space
ETC: what is the redox potential?
the tendency of an electron donor to reduce an electron acceptor, the more negative the value, the greater the tendency
What is the glycerol phosphate shuttle?
Why does it occur?
The regenration of NAD+ from NADH and FADH2 from FAD.
The inner mitochondrial membrane has a low permeability for NADH.
GPS allows the NADH synthesised in the cytosol to contribute to oxidative phosphorylation.
What are GLUT’s?
Glucose transporters on the cell surface membrane which allow glucose in by facilitated diffusion
What are alleles?
different versions of the same gene
What is the nucleosome comprised of?
8 histones, with about 200 base pairs
What is the histone code?
a layer of information overlaying the DNA, turning genes on or off
What modifies histone tails?
Histone acetyl transferases or histone de-acetylases
What happens to a woman’s X chromosomes?
One of them in inactivated (packed into tight chromatin, forming a Barr body)), balancing the differences between males and females
What is the difference between substrate level phosphorylation and oxidative phosphorylation?
SL - transfer of phosphate from a substrate to ATP
OX - forms ATP coupled to the oxidation of NADH or FADH(2)
What is the regulatory protein for red blood cells?
GATA-1, a transcription factor
Where does X inactivation occur?
In the inner cell mass of the blastocyst
