Teri goes to see her PCP after feeling depressed last couple of months. What protein transports oxygen in our body and explain its structure?

Teri goes to see her PCP after feeling depressed last couple of months as well as experiencing a seizure earlier this week. The physician orders a few test, results are shown below:

-Low hematocrit
-Low levels of Vit B12
-Low Oxygen levels
-Presence of autoantibodies against the parietal cell
-Peripheral blood smear shows abnormal RBC (large pale RBCs)After viewing the results, Teri is diagnosed with Pernicious Anemia; a condition in which autoantibodies destroys the parietal cells found within the stomach.
Address each of the following regarding Teri’s case:

-Since the parietal cell is destroyed, which substance(s) is Teri lacking as a consequence?
-What is the correlation between destruction of parietal cells and Vit B12 deficiency?
-Due to her condition, Teri lacks Pepsin. Explain why.
-If Teri were healthy, explain what her RBCs would look like?
-What is hematocrit?
-Low oxygen levels stimulate her body to create new RBCs by stimulating which process? Explain that process in depth.
-What protein transports oxygen in our body and explain its structure?
-What cell secretes antibodies and explain the various functions of antibodies.
-What are the different types of antibodies and give two characteristics for each?
-Explain the structure of an immunoglobulin.