TLS Online TPP Program

#Question id: 5647


Use the following information to answer the question. In order to test how sea urchin sperm bind to eggs, scientists isolated the egg receptor protein

that binds to the sperm acrosomal protein called bindin. Plastic beads were coated with egg receptor for bindin (ERB1) from eggs of the sea urchin Strongylocentrotus purpuratus, and then the beads mixed with sperm from S. purpuratus or from the related species, S. franciscanus. The researchers counted how many sperm were bound to each bead. The results are shown in the graph below. Treatments:

A: S. purpuratus sperm mixed with S. purpuratus ERB1 beads

B: S. purpuratus sperm mixed with beads containing no ERB1 protein

C: S. franciscanus sperm mixed with S. purpuratus ERB1 beads

D: S. franciscanus sperm mixed with beads containing no ERB1 protein

Based on the data in the graph, which of the following conclusions is supported?

#Unit 5. Developmental Biology
  1. Plastic beads will bind to sperm from both species of sea urchin.

  2. ERB1 prevents S. franciscanus sperm from binding the beads.

  3. Sperm from S. purpuratus bind to beads only if ERB1 is present.

  4. S. franciscanus and S. purpuratus are actually the same species.

More Questions
TLS Online TPP Program

#Question id: 12384

#Unit 7. System Physiology – Animal

To evaluate kidney function in a 45-year-old woman with type II diabetes, you ask her to collect her urine over 24 hours. She collects 3600 ml of urine in that period. The clinical laboratory returns the following results after analyzing the patient’s urine and plasma samples: plasma creatinine = 4 mg/dL, urine creatinine = 32 mg/dL, plasma potassium = 5 mmol/L, and urine potassium = 10 mmol/L.
What is this patient’s approximate GFR, assuming that she collected all her urine in the 24-hour period?

TLS Online TPP Program

#Question id: 12383

#Unit 7. System Physiology – Animal

Which of the following changes tends to increase urinary Ca++ excretion?

TLS Online TPP Program

#Question id: 12382

#Unit 7. System Physiology – Animal

A person with normal body fluid volumes weighs 60 kg and has an extracellular fluid volume of approximately 12.8 L, a blood volume of 4.3 L, and a hematocrit of 0.4; 57% of his body weight is water.
What is the approximate interstitial fluid volume?

TLS Online TPP Program

#Question id: 12381

#Unit 7. System Physiology – Animal

 A person with normal body fluid volumes weighs 60 kg and has an extracellular fluid volume of approximately 12.8 L, a blood volume of 4.3 L, and a hematocrit of 0.4; 57% of his body weight is water.
What is the approximate plasma volume?

TLS Online TPP Program

#Question id: 12380

#Unit 7. System Physiology – Animal

A person with normal body fluid volumes weighs 60 kg and has an extracellular fluid volume of approximately 12.8 L, a blood volume of 4.3 L, and a hematocrit of 0.4; 57% of his body weight is water. What is the approximate intracellular fluid volume?

TLS Online TPP Program

#Question id: 12379

#Unit 7. System Physiology – Animal

A healthy 29-year-old man runs a 10-km race on a hot day and becomes very dehydrated. Assuming that his antidiuretic hormone levels are very high, in which part of the renal tubule is the most water reabsorbed?