Chapter 16, Problem 1RQ

The outer one-third of the kidney is called the

A. Medulla

B. Minor calyces

C. Renal pyramid

D. Cortex

Summary Introduction

Introduction:

The two bean-shaped organs, kidneys, are located at the posterior wall of the abdominal cavity on the side of the vertebral column. A kidney can be divided into three parts in a longitudinal section. Kidneys are considered as the primary organ in the urinary system as they aid in eliminating waste.

Answer to Problem 1RQ

Correct answer:

The cortex is the outer one-third part of the kidney.

Explanation of Solution

Explanation/justification for the correct answer:

Option (d) is given as cortex. The outermost covering is called a capsule, which is a thick fiber. The layer below the capsule is known as the cortex. Cortex is the outer one-third part of the kidney, which is dark brownish in color. Also, the innermost layer is known as medulla, which consists of renal pyramids. Hence, option (d) is correct.

Explanation for the incorrect answers:

Option (a) is given as medulla. Medulla is the middle two-thirds part of the kidney, which is light colored, and hence, it cannot be the outer one-third part. So, it is an incorrect option.

Option (b) is given as minor calyces. The ureter inside the kidney expands and forms a funnel-shaped structure known as renal pelvis, which is subdivided into major calyces. This is further divided into minor calyces. Hence, it cannot be the outer one-third part of the kidney. So, it is an incorrect option.

Option (c) is given as renal pyramid. Inside the kidney, papillary ducts extend to the cortex from the calyx to form a triangular structure known as a renal pyramid. Hence, it cannot be the outer one-third part of the kidney. So, it is an incorrect option.

Hence, options (a), (b), and (c) are incorrect.

Conclusion

Therefore, it can be concluded that the cortex is the dark brown-colored outer part of the kidney.