OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

What are the two types of effector within the human body?

1. Muscle and Gland

2. Nerve and Muscle

3. Gland and Tissue

4. Muscle and Organ

The correct answer is: Muscle and Gland

The two types of effectors within the human body are indeed muscle and gland. Effectors are the components of the body that respond to signals from the nervous system, carrying out the actions that enable responses to stimuli. Muscle effectors are responsible for movement. When the nervous system sends a signal to the muscles, they contract, facilitating movement of limbs or the body as a whole. This includes both voluntary movements, like moving your arm, and involuntary movements, like your heart beating. Glands, on the other hand, are effector organs that secrete hormones or other substances necessary for bodily functions. When activated by the nervous system or other signals, glands release substances into the bloodstream or into other body cavities, contributing to processes such as digestion, metabolism, and the regulation of various bodily functions. Understanding these two types of effectors is crucial in biology, as they demonstrate how the body interacts with its environment through both movement and biochemical responses. Other options presented do not accurately represent the primary effectors recognized in the body; for instance, while nerve is essential for signaling, it is not an effector itself, and the combination of gland and tissue or muscle and organ does not accurately capture the functional roles of effectors.