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TLS Online TPP Program

#Question id: 12576

Estimates of current rates of extinction

#Unit 10. Ecological Principles
  1. Indicate that we  have reached a  state of  stable equilibrium  in  which  speciation and extinction rates are approximately equal.
  2. Suggest that one-half of all animal and plant species may be gone by the year 2100.
  3. Indicate that rates may be greater than the mass extinctions at the close of the Cretaceous period. 
  4. Indicate that only 1% of all of the species that have ever lived on Earth are still alive.
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TLS Online TPP Program

#Question id: 12219

#Unit 7. System Physiology – Animal

When the dietary intake of K+ increases, body K+ balance is maintained by an increase in K+ excretion primarily by which of the following?
TLS Online TPP Program

#Question id: 12220

#Unit 7. System Physiology – Animal

A female patient has unexplained severe hypernatremia (plasma Na+ = 167 mmol/L) and complains of frequent urination and large urine volumes. A urine specimen reveals that the Na+ concentration is 15mmol/L (very low) and the osmolarity is 155 mOsm/L (very low). Laboratory tests reveal: plasma renin activity = 3 ng angiotensin I/ml/hr (normal = 1.0), plasma antidiuretic hormone (ADH) = 30 pg/ml (normal = 3 pg/ml), and plasma aldosterone = 20 ng/dL (normal = 6 ng/dL). Which of the following is the most likely reason for her hypernatremia?
TLS Online TPP Program

#Question id: 12221

#Unit 7. System Physiology – Animal

Juvenile (type I) diabetes mellitus is often diagnosed because of polyuria (high urine flow) and polydipsia (frequent drinking) that occur because of which of the following?
TLS Online TPP Program

#Question id: 12222

#Unit 7. System Physiology – Animal

In acidosis, most of the hydrogen ions secreted by the proximal tubule are associated with which of the following processes?
TLS Online TPP Program

#Question id: 12275

#Unit 7. System Physiology – Animal

Two weeks after constricting the renal artery of a sole remaining kidney to initially reduce renal artery pressure by 20 mm Hg (from 100 to 80 mm Hg), which of the following changes would you expect, compared with before constriction of the artery?
TLS Online TPP Program

#Question id: 12276

#Unit 7. System Physiology – Animal

Because the usual rate of phosphate filtration exceeds the transport maximum for phosphate reabsorption, which of the following is true?