LocomotionAct, ability, or power of movingThe musculoskeletal system gives animals the ability to moveProvides form, support, stability, and movement to eh body
BonesMade of collagen and calcium saltsBones change shape when osteoblasts (bone-building cells) and osteoclasts (bone-breaking cells) remodel them.Joints are held together by ligamentsThe connective tissue that attach muscles to bones are tendons.
ExoskeletonEncloses the bodies of arthropodsSupports the important internal organs and protects them from being damagedInsects shed their exoskeleton to increase in size
EndoskeletonFound in all vertebratesMade up of phosphate and calciumImportant to maintain the body shape, supports the soft-body tissues and protects the internal organs from getting injuredCertain parts store minerals
HydrostaticConsists of internal body fluids in the confined body cavityThe fluid is held under pressure in compartments and surrounded by musclesThis ensures the shape of soft-bodied organisms like earthworms and sea anemones.
Axial SkeletonIs the part of the skeleton that forms an imaginary line down the back bone of the bodyIs made out of-skull-vertebral column-sternum and ribs
Appendicular SkeletonScapula- flat, triangular-shaped bone that forms the basis of the shoulderHumerus- articulates with the scapula to form a ball-end socket joint at the shoulderUlna- longer bone of the forearm that articulates with the humerusRadius- flattened, slightly curved bone in the handPelvic Girdle- provides connection between the axial skeleton and hind limbsFemur- largest bone in the human body. Forms a hind joint at the kneeFibula- shorter and smaller bone, giving support to the leg
An organ system consisting of skeletal, smooth, and cardiac musclesIt permits movement of the body, maintains posture, and circulates blood throughout the bodyMuscle cells (fibers) move by lengthening and contracting, a process that generates much of the body heat needed for survivalMuscular System
Three Types of Muscle Skeletal MuscleSmooth or Visceral MuscleCardiac MuscleMuscle
Striated voluntary musclesAttached to bones by dense, fibrous connective tissue called tendonsImportant in maintaining posture, providing support and allowing for movementSkeletal Muscle
Muscles are made up of muscle bundles, which subdivide into muscle fasciclesWithin each muscle fascicle are units called muscle fiber cellsWithin each muscle fiber are contractile fibrils called myofibrilsA single myofibril is subdivided intro sarcomomeres or contractile unitsOrganization of Skeletal muscle
The functional unit in a muscle cellInside a sarcomere, there are two protein filamentsActin: thin filamentMyosin: thick filamentInteraction of both proteins cause muscle contractionsSarcomere
Found in the heartIts action is beyond conscious controlWhen the skeletal muscles are exercised, they send signals to the heart via nerve cells to provide more oxygen
Found throughout the body (in the walls of blood vessels, the digestive tract, and internal organs)InvoluntaryThey respond to demands for increased oxygen from the skeletal muscles by narrowing or widening blood vesselsSmooth Muscle
Tendons are tough bands of fibrous connective tissue that usually connect muscle to boneLigaments refer to fibrous tissue that connect bones to other bonesEx: head and neck, wrist, thorax, pelvis, kneeLigaments
A nerve impulse is sent to a skeletal muscle.The neuron sending the impulse releases a neurotransmitter onto the muscle cell.The muscle depolarizes.Depolarization causes the sarcoplasmic reticulum to release calcium ions.These calcium ions cause the actin and myosin filaments to slide past each other.The muscle contracts.How does a muscle contract?
Hydrostatic SkeletonMany invertebrates have these skeletons.As mentioned earlier, three types of skeletons: exoskeleton, endoskeleton, and hydrostatic skeleton.
How it WorksExterior muscles contract along the body of the organism, causing the fluid filled chamber inside to move.Similar to peristalsis in the human intestine.
NematodesLocomotion in nematodes
RoundwormsImportant: Nematodes and annelids have a one way digestive track although they are invertebrates
AnnelidsEarthworms are annelidsHave better locomotion than nematodes because they are segmented, so they can control their peristaltic waves of motion better.