Topic 13: Movement functions of animals, support and locomotor system of man

Type of Muscle: Some

Skeletal Muscle:

• is responsible for voluntary movements of the body

• striated (marked with thin parallel lines) with multiple nuclei per cell - precise and efficient contraction for powerful and controlled movements

• Have multiple nuclei per cell due to cell fusion of myoblasts during cell development - single elongated cell with multiple nuclei - enhanced ability to produce proteins and enzymes for muscle contraction, repair and growth

Under concious control

Type of Muscle: Can

Cardiac Muscle:

• Found only in the heart, responsible for pumping blood

• lined with thin parallel lines with single nucleus per cell, with intercalcated disks that are adhesive junctions holding muscle cells toether. Prevent cells from separating during intense mech stress of heart

• higher density of mitochondria to prodice ATP

Type of Muscle: Sing

Smooth muscle:

• found in the calls of internal organs like the stomach, intestines, and blood vessels, controlling involuntary movements

• non striated with single nucleus per cell

• involuntary control - automatic nervous system (hormones can have effect like during childbirth - slower and more sustained movements, wave like movements)

mechanism of contraction of skeletal muscle

Sliding filament theory

1. At the NEURO_MUSCULAR Juction, where nerve cell connects to muscle fiber, a nerve impulse signal travels own the motor neuron (nerve cell) to the neuromuscular junction and released ACh (chemical messenger)

2. ACh binds to mucle cell membrane receptors that triger action potential - spreading along the muscle fiber like a wave

3. ACh travels down the T-tubules (tiny tunnels in muscle cell) causing SARCOPLASMIC RETICUULUM to release calcium

4. calcium ions binds to a protein which causes another protein to move and expose binding site where myosin heads attatch forming cross bridges. These heads move pulling filaments causing the muscle to contract

5. ATP binds of myosin causing detachment

Upper body: Please Dont Bonb Triceratops

Pectorlis Major

• chest muscles - push

Deltoids

• shoulder muscles

Biceps Brachii

• flex elbow

Triceps Brachii

• extend elbow

Core: ROE

Rectus Abdominus:

• abs

Obliques: slide muscles, responsible for trunk rotation

Erector spinae: Muscles along the spine: back extention

lower body: Quails Hug Goats Gastronomically

Quadriceps:

• front of the thigh extending the knee

hamstrings:

• back of the thigh, flexes the knee

Gluteus Maximum

• buttocks responsibe for hip extension

Gastronemius:

• calf musle: flexing of foot

Bone structure

Made of connective tissue, reinforced with calcium and specialized bone cells

206 bones

• compact bone - dense outer layer for strength and protection

• spongey bone - lightweight and porous inner layer for containing bone marrow

• bone marrow (most) - produces blood cells (red marrow) and stores fat (yellow)

Types of bones

• long bones: found in the arms and legs (femur, humerus)

• short bones: found in wrists and anke (capals, tarsals)

• Flat bones: skull, ribs pelvis

• Irreguar bones: have complex shapes, vertebrae

the skeleton

• Skull – including the jaw bone

• Spine – cervical, thoracic and lumbar vertebrae, sacrum and tailbone (coccyx)

• Chest – ribs and breastbone (sternum)

• Arms – shoulder blade (scapula), collar bone (clavicle), humerus, radius and ulna

• Hands – wrist bones (carpals), metacarpals and phalanges

• Pelvis – hip bones

• Legs – thigh bone (femur), kneecap (patella), shin bone (tibia) and fibula

• Feet – tarsals, metatarsals and phalanges.

joints

connect bones and allow movement:

• ball and socket joints - movement in multiple directions (shoulder hip)

• Hinge join - one direction (elbow, knee)

• Pivot joints: allow rotational movement (neck)

• Gliding joints: allow bonds to slide past each other, write and ankles