Podcast
Questions and Answers
The sliding filament model of contraction involves ________.
The sliding filament model of contraction involves ________.
actin and myosin sliding past each other and partially overlap
Identify the correct sequence of the following events.
Identify the correct sequence of the following events.
Which type of muscle requires voluntary nervous stimulation for activation?
Which type of muscle requires voluntary nervous stimulation for activation?
Skeletal
The contractile, or functional, unit of a muscle fiber is __________.
The contractile, or functional, unit of a muscle fiber is __________.
Signup and view all the answers
Muscle tissue has all of the following properties EXCEPT________.
Muscle tissue has all of the following properties EXCEPT________.
Signup and view all the answers
What would result from a block in the release of neurotransmitters into a neuromuscular synapse?
What would result from a block in the release of neurotransmitters into a neuromuscular synapse?
Signup and view all the answers
What prevents ACh in the synaptic cleft from continuing to stimulate contraction after nervous stimulation stops?
What prevents ACh in the synaptic cleft from continuing to stimulate contraction after nervous stimulation stops?
Signup and view all the answers
What part of the sarcolemma contains acetylcholine receptors?
What part of the sarcolemma contains acetylcholine receptors?
Signup and view all the answers
One of the important functions of skeletal muscle contraction is the production of heat.
One of the important functions of skeletal muscle contraction is the production of heat.
Signup and view all the answers
The effect of a neurotransmitter on the muscle cell membrane is to modify its ion permeability properties temporarily.
The effect of a neurotransmitter on the muscle cell membrane is to modify its ion permeability properties temporarily.
Signup and view all the answers
What describes a fascicle?
What describes a fascicle?
Signup and view all the answers
The __________ shorten(s) during muscle contraction.
The __________ shorten(s) during muscle contraction.
Signup and view all the answers
What are the symptoms of curare poisoning?
What are the symptoms of curare poisoning?
Signup and view all the answers
Which of the following is most directly required to initiate the coupling of myosin to actin?
Which of the following is most directly required to initiate the coupling of myosin to actin?
Signup and view all the answers
When a sarcomere contracts and thin filaments move over thick filaments, you would expect to see ________.
When a sarcomere contracts and thin filaments move over thick filaments, you would expect to see ________.
Signup and view all the answers
What step precedes all of the other listed steps in muscle contraction?
What step precedes all of the other listed steps in muscle contraction?
Signup and view all the answers
Which term best identifies a muscle cell?
Which term best identifies a muscle cell?
Signup and view all the answers
Myoglobin ________.
Myoglobin ________.
Signup and view all the answers
The sliding filament model of contraction states that __________.
The sliding filament model of contraction states that __________.
Signup and view all the answers
A resting potential is caused by a difference in the concentration of certain ions inside and outside the cell.
A resting potential is caused by a difference in the concentration of certain ions inside and outside the cell.
Signup and view all the answers
Study Notes
Sliding Filament Model
- Actin and myosin filaments slide past each other during muscle contraction, resulting in partial overlap.
Sequence of Muscle Contraction Events
- Calcium ions (Ca+) bind to troponin.
- Troponin then removes tropomyosin from G-actin.
- Myosin binds to actin.
- Myosin generates a power stroke.
- Sarcomere shortens.
- ATP recharges the myosin head.
Skeletal Muscle Characteristics
- Requires voluntary stimulation from the nervous system for activation.
- Neuromuscular junction is the communication site between nerve fiber and muscle fiber.
- Sarcomere is the smallest functional unit of muscle, located between two Z discs.
Properties of Muscle Tissue
- Muscle tissue exhibits contractility, excitability, and extensibility.
- Secretion is NOT a property of muscle tissue.
Impact of Toxins
- Toxins blocking neurotransmitter release lead to muscle contraction loss due to lack of acetylcholine (ACh).
ACh Regulation
- Acetylcholinesterase degrades ACh in the synaptic cleft, ceasing stimulation of muscle contraction.
Muscle Structure
- Epimysium is a dense connective tissue around muscles, connecting tendons to bones or other muscles.
- A fascicle is a group of muscle fibers enclosed by perimysium.
Muscle Contraction Facts
- Skeletal muscle contractions produce heat.
- Actin is the primary protein in thin myofilaments.
Ion Permeability and Neurotransmitters
- Neurotransmitters modify muscle cell membrane ion permeability temporarily.
Sarcomere Changes During Contraction
- During contraction, the sarcomere shortens as actin slides over myosin, leading to smaller I bands.
Muscle Cell Types
- Muscle fibers are multinucleated cells formed by the fusion of skeletal muscle cells during development.
Myoglobin Function
- Myoglobin is a protein that stores oxygen within muscle cells, supporting aerobic metabolism.
Connective Tissue Layers
- Endomysium surrounds individual muscle cells, while perimysium encloses fascicles.
Cross-Bridge Formation
- Cross-bridges form between actin (thin filaments) and myosin (thick filaments) during contraction.
Muscle Tissue Types
- Skeletal muscle is voluntarily controlled.
- Cardiac muscle is involuntary and striated.
- Smooth muscle is involuntary and typically non-striated.
Sliding Filament Theory
- During contraction, thin myofilaments slide past thick myofilaments, leading to increased overlap between actin and myosin.
Resting Potential
- A resting potential arises due to ionic concentration differences across the cell membrane, crucial for nerve impulse transmission.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on the sliding filament model and muscle contraction events with these flashcards. Learn the sequence of key events involved in muscle contraction, including the roles of myosin, actin, and calcium ions. Perfect for students studying physiology or anatomy.
