In 1988, Richardson and Richardson observed that certain amino acid residues are statically favored as the amino-terminal caps for the alpha helices in 45 globular proteins. Which of the following statement stand correct with stability of helix?

A. The introduction of a negatively charged side chain at the N-cap, which can neutralize the partial dipole created by the unpaired amide protons, has been shown to increase stability

B. In particular, Gly is often observed at the both C-cap position and N-cap positions

C. In particular, Gly is often observed at the C-cap position only

D. In particular, Gly is often observed at the C-cap position, Asn at the N-cap position, Pro at the Ncap+1 and Asp and Glu at N2 and N3

#Question id: 10939

#Unit 7. System Physiology – Animal

After a person is placed in an atmosphere with low oxygen, how long does it take before there are increased numbers of reticulocytes?

#Question id: 10925

#Unit 7. System Physiology – Animal

During the second trimester of pregnancy, where is the predominant site of red blood cell production?

#Question id: 10926

#Unit 7. System Physiology – Animal

Following a blood donation, red cell production begins to increase in

#Question id: 10927

#Unit 7. System Physiology – Animal

A 62-year-old female arrives for her annual physical. She complains of itching in her hands along with headaches and vertigo. A routine complete blood count (CBC) shows red blood cells (RBCs) of 8.2 million/μl, white blood cells (WBCs) 37,000/μl, and platelets 640,000/μl. Her erythropoietin levels are lower than normal. The primary diagnosis would be

#Question id: 10928

#Unit 7. System Physiology – Animal

A 40-year-old woman visits the clinic complaining of fatigue. She had recently been treated for an infection. Her laboratory values are RBC 1.8 × 106/μl, Hb 5.2 g/dL, hematocrit (Hct) 15, WBC 7.6 × 103/μl, platelet count 320,000/μl, mean corpuscular volume (MCV) 92 fL, and reticulocyte count 24%. What is the most likely explanation for this presentation?

#Question id: 10930

#Unit 7. System Physiology – Animal

A 34-year-old man with schizophrenia has had chronic fatigue for 6 months. He has a good appetite, but has refused to eat vegetables for 1 year because he hears voices saying that vegetables are poisoned. His physical and neurological examinations are normal. His hemoglobin level is 9.1 g/dL, leukocyte count is 10,000/μl3, and MCV is 122. Which of the following is the most likely diagnosis?