Cell cycle is regulated by master regulators (cyclin and CDKs). In vertebrates, G1 CDK activity rises during G1 and is stimulated by the presence of growth factors. When signaling from growth factors is sustained, the resulting cyclin D–CDK4/6 complexes begin phosphorylating Rb, releasing some E2F, which stimulates transcription of the genes encoding cyclin E, CDK2, and E2F itself. In a particular cell type there is a mutation in Rb such that it cannot be phosphorylated. What will be the correct expression pattern of cyclin E in these cells after mitotic stimulation?

#Question id: 11016

#Unit 7. System Physiology – Animal

A ventricular depolarization wave when traveling −90° in the frontal plane will cause a large negative deflection in which lead?

#Question id: 11017

#Unit 7. System Physiology – Animal

Which of the following is most likely at the “J point” in an EKG of a patient with a damaged cardiac muscle?

#Question id: 11018

#Unit 7. System Physiology – Animal

A 50-year-old man has a blood pressure of 140/85 and weighs 200 lb. He reports that he is not feeling well, his EKG has no P-waves, he has a heart rate of 46, and the QRS complexes occur regularly. What is his likely condition?

#Question id: 11019

#Unit 7. System Physiology – Animal

An 80-year-old man had an EKG taken at his local doctor’s office, and the diagnosis was atrial fibrillation. Which of the following statements are likely conditions in someone with atrial fibrillation?

#Question id: 11020

#Unit 7. System Physiology – Animal

Circus movements in the ventricle can lead to ventricular fibrillation. Which of the following conditions in the ventricular muscle will increase the tendency for circus movements?

#Question id: 11021

#Unit 7. System Physiology – Animal

A 75-year-old man goes to the hospital emergency department and faints. Five minutes later he is alert. An EKG shows 75 P waves per minute and 35 QRS waves per minute with a normal QRS width. Which of the following is the likely diagnosis?