Muscle Structure Worksheet
A Grade 9 science worksheet exploring the structure and function of muscle tissue, including types of muscle, their components, and how they contract.
Includes
Standards
Topics
Muscle Structure Exploration
Name:
Date:
Score:
Read each question carefully and provide your best answer. For multiple choice questions, circle the correct option. For fill-in-the-blank, write the word(s) that best complete the sentence.
1. Which type of muscle tissue is responsible for voluntary movements?
Cardiac muscle
Smooth muscle
Skeletal muscle
All of the above
2. What is the basic contractile unit of a muscle fiber?
Myofibril
Sarcomere
Actin
Myosin
3. The thin filaments in a sarcomere are primarily composed of the protein .
4. The specialized endoplasmic reticulum in muscle cells that stores calcium ions is called the .
5. Muscle contraction is initiated by the release of ions from the sarcoplasmic reticulum.
6. Briefly explain the 'sliding filament theory' of muscle contraction.
7. Differentiate between slow-twitch and fast-twitch muscle fibers, providing one characteristic for each.
8. Observe the diagram of a muscle fiber cross-section below. Identify the structures labeled A, B, and C.

A:
B:
C:
9. Tendons connect muscle to bone.
True
False
10. Cardiac muscle tissue is found in the walls of the stomach and intestines.
True
False