Search Header Logo
3.6.3 Skeletal muscles

3.6.3 Skeletal muscles

Assessment

Flashcard

Biology

12th Grade

Practice Problem

Hard

Created by

Ross Kearns

FREE Resource

Student preview

quiz-placeholder

15 questions

Show all answers

1.

FLASHCARD QUESTION

Front

What is the primary function of antagonistic muscle pairs?

Back

To work against each other to move bones

Answer explanation

Antagonistic muscle pairs work against each other to create movement by contracting and relaxing, allowing bones to move at joints. This is essential for coordinated motion, making the correct answer 'To work against each other to move bones'.

2.

FLASHCARD QUESTION

Front

What best describes the ultrastructure of a myofibril?

Back

A bundle of actin and myosin filaments

Answer explanation

A myofibril is best described as a bundle of actin and myosin filaments, which are the key proteins involved in muscle contraction. This structure is essential for the function of muscle fibers.

3.

FLASHCARD QUESTION

Front

What role does calcium ions play in myofibril contraction?

Back

They bind to tropomyosin to expose binding sites

Answer explanation

Calcium ions bind to tropomyosin, causing a conformational change that exposes the binding sites on actin for myosin. This is crucial for initiating muscle contraction.

4.

FLASHCARD QUESTION

Front

Which molecule is directly responsible for the power stroke in muscle contraction?

Back

ATP

Answer explanation

ATP is crucial for muscle contraction as it provides the energy needed for the myosin heads to perform the power stroke, pulling actin filaments and causing muscle shortening.

5.

FLASHCARD QUESTION

Front

What is the role of phosphocreatine in muscle contraction?

Back

It provides a rapid source of ATP

Answer explanation

Phosphocreatine serves as a rapid source of ATP during muscle contraction, allowing for quick energy replenishment. This is crucial for sustaining high-intensity activities, making it essential for muscle function.

6.

FLASHCARD QUESTION

Front

Characteristic of slow skeletal muscle fibres?

Back

They have a high density of mitochondria

Answer explanation

Slow skeletal muscle fibres are characterized by a high density of mitochondria, which supports endurance activities by providing sustained energy. In contrast, they fatigue slowly and are not primarily used for short bursts of power.

7.

FLASHCARD QUESTION

Front

Where are fast skeletal muscle fibres typically located?

Back

In muscles used for quick, powerful movements

Answer explanation

Fast skeletal muscle fibers are primarily found in muscles responsible for quick, powerful movements, such as sprinting or weightlifting, due to their ability to contract rapidly and generate high force.

Access all questions and much more by creating a free account

Create resources

Host any resource

Get auto-graded reports

Google

Continue with Google

Email

Continue with Email

Classlink

Continue with Classlink

Clever

Continue with Clever

or continue with

Microsoft

Microsoft

Apple

Apple

Others

Others

Already have an account?