Developing sperm cells are protected by a blood-testis barrier formed by
A. connective tissue septa.
B. interstitial spaces.
C. Leydig cells.
D. sustentacular cells.
E. leukocytes.
D
You might also like to view...
The following is a particular sequence of base triplet on a DNA molecule: ATG. What is the corresponding codon for the mRNA?
a) TAC b) GUA c) GTA d) CTA e) UAC
Choose the one trait that does not characterize the structure of a nephron.
A) There are two coiled portions of the renal tubule. B) The glomerular capsule contains podocytes and slit pores. C) Blood that will be filtered flows into the glomerular capsule. D) Several nephron tubules merge to form a collecting duct.
What is the optimal pH level for pepsin activity?
A) 3—4 B) 10—13 C) 1—3 D) 7
Which tissue contains an extensive extracellular matrix?
A. Nervous B. Connective C. Epithelial D. Muscle