True Brains and Spinal Cords Occurred First in

question 56

Multiple Choice

True brains and spinal cords occurred first in 

• A)chordates. 
• B) mollusca.​ 
• C)crustacean. 
• D)hemichordates.

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Definitions:

Semen Volume

The total volume of fluid ejaculated, containing sperm and fluids from the seminal vesicles, prostate, and other sex glands.

Seminal Vesicles

Glands that produce seminal fluid, a component of semen, which provides nutrients and a medium for sperm during ejaculation.

Prostate Gland

A gland in the male reproductive system that produces seminal fluid, which nourishes and transports sperm.

Penis

The external male genital organ involved in sexual intercourse and urination.