Animal Movement

Pseudopodia

temporary projection used by amoeba for movement

Flagella

appendage made by microtubules for flagellate movement; few and long

Cilia

hair-like projection used by ciliates for movement; many and short

Myocytes

muscle cells specialized for contraction

Myosin

thick fiber w cross bridges

Actin

thin fiber

How do myocin and actin interact for muscle contraction?

sliding filament theory. actin has bonding sites for myosin cross bridges, which open by calcium. as actin slides along myosin bridge, the cell shortens

Smooth muscle

found in tubes (blood vessels, gut); involuntary contraction

Skeleton muscle

attaches to the skeleton; voluntary movement; striated

Cardiac msucle

in heart; involuntary contraction (e.g. heart pumping); striated

Tendons

Tissue connecting muscle to bone → muscles pulls on tendon, which pulls on the bone

Ligaments

Tissue connecting bone to bone, stabilizing joints

How to antagonists and agonists interact in movement?

antagonist: relaxes allowing movement; controls speed and stability

agonist: contracts creating movement

Muscular hydrostats

locomotion without skeleton → elephant trunks, tongues, worms