G protein‑coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs) are two basic receptor types by which cells transduce s
ignals. A) Classify each statement as describing GPCRs, RTKs, both types of receptors, or neither of these two types.
1. phosphorylation of receptor can terminate signal or desensitize receptor.
2. autophosphorylation of receptor can initiate signal.
3. structure contains seven transmembrane helices.
4. an example is the insulin receptor.
5. an example is the epinephrine receptor.
6. activate heterotrimeric G proteins directly.
G Protein Coupled Receptors(GPCRs) are more common and found in almost all eukaryotes whereas Receptor Tyrosine Kinases(RTKs) are second largest family of receptors that relay signal from cell surface to the interior
G protein coupled receptors(GPCRs) interacts with the ligand activated GPCR and phosphorylates its intracellular domain.This process of phosphorylation can terminate signal or desensitize receptor
Autophosphorylation of receptor can initiate signal in case of Receptor Tyrosine Kinases(RTKs);Autophosphorylation is a feature of RTKs in which receptor dimerization activates intrinsic tyrosine kinase activity by which they phosphorylate its own tyrosine residue on cytosolic phase
Seven transmembrane helices can be seen in case of G protein-coupled receptors(GPCRs);transmembrane protein of it consists of single polypeptide and spans the membrane 7 times
Insulin receptor is a part of Insulin Signalling which comes under RTKs;Insulin receptor always exist in case of dimeric form
Epinephrine receptor is an example of GPCRs;Epinephrine is an endocrine hormones produced in stress condition
Transmembrane protein of GPCR activates G protein,activated G protein binds with effector enzyme and activate it;effector enzyme further can produce or destroy secondary messenger
During pregnancy the fetus depends on its mother for nourishment and oxygen since it cannot breathe air it's blood circulates differently than it does after birth.
Due to the circumstances stated above the mothers womb develops an organ known as the placenta that develops and implants in the mother's womb during pregnancy to provide oxygen and nutrients to the growing baby and remove waste products from the baby's blood
The fetus is connected to the placenta by the umbilical cord which contains blood vessels that transport nutrients and oxygen from the mothers blood to the baby and also transports waste products and carbon dioxide from the baby to the placenta and then to the mothers circulatory system to be eliminated.
When people have anemia, their body doesn't produce enough red blood cells. They don't get enough oxygen, which makes them feel fatigued and can also cause serious health complications.
More commonly, an X chromosome will die and get replaced by a Y chromosome (all humans start off as females). When this occurs, the substitute Y chromosome causes changes in the zygote to occur; they begin developing male genitalia (i.e. penises, testicles, prostates, etc.).
