BIOL1003 Lecture 5: Lecture 5 BIOL - Muscular System
9 Aug 2018
School
Department
Course
Professor
19th March
BIOL Lecture
Learning Outcomes
➢ Describe the three types of muscle tissue
➢ Explain the sliding philament theory of muscle contraction
1. Describe the three types of muscle tissue
Skeletal Muscle is mainly voluntary
- Way you can recognise skeletal muscle – long straight
unbranched fibres
- Where the fibres running through the muscle overlap, they
cause strips 90 degrees to the length of the muscle cells.
- The stripes are striations.
- Mifibril cells retain multiple nuclei
- What type of muscle is it and why?
Smooth muscle – generally involuntary
- Doesn’t have striation muscles because there’s no overlap
- Look for a spindle shape
- There are fibres that run in a criss-cross fashion which allows
the muscle to contract.
Cardiac
- Look for branching
- Also have striations as the fibres run in a similar fashion to
skeletal muscles.
- Where the junctions of cardiac muscles joined together,
intercalated discs exist.
- Most cardiac cells have one nuclei per cell
Muscles are also a reservoir for blood, get a lot of blood supply so
it gets the oxygen it needs to power the muscles.
Muscle tissue can repair itself much quicker than other tissues
because it contains the blood.
Striations and Microfilaments
How is structured related to function
- Sliding Filament Theory –
- sarcomere (anything to do with the skeleton or skeletal
muscle) and contain microfilaments inside.
➢ Thin and thick filaments
➢ Thick filament is made up of a protein called myosin
(myo – muscle)
➢ Thin made up of actin – (actin is very prevalent in the
sarcomere)
Describe how the sarcomere contracts.
Myosin grabs onto the actin and pulling into the middle of the H Zone.
Extension 0 increasing the angle between two movable bones.
Flection – decreasing the angle between two movable joints.
What make the myosin reach up?
Document Summary
Describe the three types of muscle tissue. Explain the sliding philament theory of muscle contraction: describe the three types of muscle tissue. Way you can recognise skeletal muscle long straight. Where the fibres running through the muscle overlap, they unbranched fibres cause strips 90 degrees to the length of the muscle cells. Doesn"t have striation muscles because there"s no overlap. There are fibres that run in a criss-cross fashion which allows the muscle to contract. Also have striations as the fibres run in a similar fashion to skeletal muscles. Where the junctions of cardiac muscles joined together, intercalated discs exist. Most cardiac cells have one nuclei per cell. Muscles are also a reservoir for blood, get a lot of blood supply so it gets the oxygen it needs to power the muscles. Muscle tissue can repair itself much quicker than other tissues because it contains the blood.
