TLS Online TPP Program

#Question id: 12095


It is now thought that the atmosphere of the primitive Earth was composed largely of carbon dioxide, nitrogen, and water vapor. The composition of certain iron-containing minerals suggests that the carbon dioxide began to be replaced by oxygen about 2 billion years ago.   Which of the following is the best explanation for the change in atmospheric composition?

#Unit 10. Ecological Principles
  1. Ozone produced in the upper atmosphere by ultraviolet light broke down to oxygen. 
  2. Minerals such as iron oxide released oxygen into the atmosphere.
  3. Oxygen was present in volcanic gases and slowly accumulated with time. 
  4. Photosynthesis was established in primitive bacteria.
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TLS Online TPP Program

#Question id: 10970

#Unit 7. System Physiology – Animal

A mother of blood type A+ who has always been perfectly healthy just delivered her second child. The father is of blood group O−. Knowing that the child is of blood group O− (O, Rh−), what would you expect to find in this child?

TLS Online TPP Program

#Question id: 10971

#Unit 7. System Physiology – Animal

A pregnant woman comes in for a visit. She is AB Rh− and her husband is A Rh+. This is her first child. What should be done at this time?

TLS Online TPP Program

#Question id: 10972

#Unit 7. System Physiology – Animal

What is the proper pathway for the extrinsic clotting pathway?

TLS Online TPP Program

#Question id: 10973

#Unit 7. System Physiology – Animal

An 11-year-old premenstrual female presents with a painful knee after mild trauma. Upon further evaluation you observe soft tissue bruises. The child is an orphan and there is no family history. The foster mother reports no other problems. The aPTT is prolonged and the PT is normal. A complete hematologic workup would yield

TLS Online TPP Program

#Question id: 10975

#Unit 7. System Physiology – Animal

A teenaged boy with numerous nosebleeds was referred to a physician for evaluation prior to a minor surgery. His prothrombin time (PT) was 11 sec (11–15 sec normal), partial thromboplastin time (PTT) was 58 sec (25–40 sec normal), and bleeding time was 6.5 min (2–7 min normal). Which of the following is most likely abnormal in this young man?

TLS Online TPP Program

#Question id: 10974

#Unit 7. System Physiology – Animal

A 63-year-old woman returned to work following a vacation in New Zealand. Several days after returning home, she awoke with swelling and pain in her right leg and her leg was blue. She went immediately to the emergency room where an examination showed an extensive deep vein thrombosis involving the femoral and iliac veins on the right side. Following resolution of the clot, this patient will require which treatment in the future?