Nervous System Activity Sheet - Free Printable

Problem Analysis:

The provided image contains a worksheet on the Nervous System. The tasks include multiple-choice questions, word selection, definitions, and labeling of a diagram. Below is a detailed solution for each part of the worksheet.

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1. Choose the correct answer.

#### A. This is the largest sense organ through which sweat is excreted.
- Options:
- a. nose
- b. eye
- c. ear
- d. skin

Explanation:
The skin is the largest organ in the human body and plays a crucial role in regulating body temperature by excreting sweat through sweat glands. Sweat helps cool the body down when it overheats.

Correct Answer: d. skin

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#### B. Which of the following is the largest part of the brain?
- Options:
- a. cerebellum
- b. cerebrum
- c. medulla
- d. none of these

Explanation:
The cerebrum is the largest part of the brain. It is responsible for higher functions such as thinking, memory, sensory perception, and voluntary movement. The cerebellum coordinates movement, and the medulla controls basic life functions like breathing and heart rate.

Correct Answer: b. cerebrum

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#### C. The following nerve carries messages from the ear to the brain.
- Options:
- a. optic nerve
- b. auditory nerve
- c. olfactory nerve
- d. motor nerve

Explanation:
The auditory nerve (also known as the vestibulocochlear nerve) carries signals from the inner ear to the brain, conveying information about sound and balance. The optic nerve carries visual information, the olfactory nerve carries smell signals, and motor nerves control muscle movements.

Correct Answer: b. auditory nerve

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2. Tick (√) the correct word.

#### a. An instant action shown by the body to protect oneself from injury is known as (reflex / neuron).
- Options:
- reflex
- neuron

Explanation:
A reflex is an automatic, involuntary response to a stimulus, such as pulling your hand away from a hot surface. A neuron is a nerve cell that transmits signals in the nervous system but does not describe an action.

Correct Answer: reflex

#### b. The (nervous / skeletal) system controls all the other systems of our body.
- Options:
- nervous
- skeletal

Explanation:
The nervous system is responsible for controlling and coordinating all bodily functions, including movement, sensation, and regulation of internal processes. The skeletal system provides structural support but does not control other systems.

Correct Answer: nervous

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3. Define.

#### a. Neurons
- Definition:
Neurons are specialized cells in the nervous system that transmit electrical and chemical signals throughout the body. They are responsible for processing information and communicating with other neurons, muscles, and glands.

#### b. Spinal cord
- Definition:
The spinal cord is a long, tube-like structure made up of bundles of neurons and supporting tissues. It extends from the base of the brain down the back and serves as a major pathway for transmitting signals between the brain and the rest of the body.

#### c. Reflex action
- Definition:
A reflex action is an automatic, involuntary response to a stimulus. It occurs quickly without conscious thought and is controlled by the spinal cord or brainstem. Examples include blinking your eyes or withdrawing your hand from a hot object.

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4. Label the diagram and answer the following.

#### Diagram Labeling:
The diagram shows a cross-section of the brain. Here are the labels for the colored regions:

1. Blue region: Cerebrum
- Explanation: The largest part of the brain, responsible for higher functions like thinking, memory, and voluntary movement.

2. Yellow region: Cerebellum
- Explanation: Involved in coordination, balance, and fine motor skills.

3. Green region: Brainstem
- Explanation: Connects the brain to the spinal cord and controls basic life functions like breathing and heart rate.

4. Pink region: Limbic system
- Explanation: Associated with emotions, memory, and motivation.

5. Orange region: Hypothalamus
- Explanation: Regulates body temperature, hunger, thirst, and other homeostatic functions.

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Final Answers:

1. Choose the correct answer.
- A. d. skin
- B. b. cerebrum
- C. b. auditory nerve

2. Tick (√) the correct word.
- a. reflex
- b. nervous

3. Define.
- a. Neurons: Specialized cells in the nervous system that transmit electrical and chemical signals.
- b. Spinal cord: A long, tube-like structure extending from the brain, serving as a major pathway for signals between the brain and the rest of the body.
- c. Reflex action: An automatic, involuntary response to a stimulus.

4. Label the diagram.
- Blue: Cerebrum
- Yellow: Cerebellum
- Green: Brainstem
- Pink: Limbic system
- Orange: Hypothalamus

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Final Answer Box:

\[
\boxed{
\text{1. A: d, B: b, C: b; 2. a: reflex, b: nervous; 3. Definitions provided; 4. Labels: Cerebrum, Cerebellum, Brainstem, Limbic system, Hypothalamus.}
}
\]