2 20 Notes 20 02 2014 09 51 00 Breast feeding after birth pituitary secretes prolactin stimulates milk synthesis after 2 days and a release of colostrum high protein body content 15 25 lobules contain milk secreting alveoli that connect through sucking stimulates nipple nerve response causes oxytocin release ducts to the nipple which lobules contract and milk flows into the ducts areola area that is stimulated Lactation suckling by infant stimulates mechano recepteors in nipple sends nerve impulses to hypothalamus in the brain its the interaction center b w physical and chemical contact aka nerves and hormones hypothal Signals pituitary to release oxytocin oxytocin stimulates breast contraction of tissue milk is released into ducts positive feedback oxytocin from pituitary stimulates pair bonding friendship cuddle hormone oxytocin is a 9 amino acid circular polypeptide PROTEIN that s made by pituitary causes warm feelings maternal behavior bonding with baby hormone associated with love cuddling affection low levels promiscuous partnerships and high levels 1 to 1 pair bonding these levels increase a TON 3 x more in men 10 x more in women pleasure reward for reproducing Childhood Puberty growth is quickest during first few months overtime you go from a giant baby head to one that is proportional to your body Skeleton two parts axial skeleton central building structure straight up and down like spine skull and the appendicular skeleton things that hang off the sides like your shoulders and pelvis central structure shoulders hips bone functions 1 Movement 2 Support 3 Protection 4 Mineral storage 5 Blood cell formation storage and retrieval like a bank of calcium bone marrow where all of your blood cells are made so your immune system starts here and your health is regulated bones heal steps 1 a good supply of blood hematoma formation 2 Blood vessels grow and callus form 3 Bony callus formation occurs 4 Bone is remodeled and it s healed use casts to keep pieces together while blood vessels start to grow Knee hinge joint is lubricated with cartilage between femur and tibia LCL lateral collateral ligament and on the side ACL anterior cruciate ligament and on the front stress in opposite directions tearing it OR damage to shock absorbing cartilages in the knee Arthritis breakdown of cartilage between the bones in joints bones rub together pain swelling stiff 2 types osteoarthritis wearing out in weight bearing joints or hands feet more common in younger men and more common in older women after aging obesity highest factor and can be caused be injuries infections too osteo Later o activities that REPETITIVELY impact same spot of cartilage RA autoimmune disease inflammation rheumatoid arthritis of membranes cartilage bone shape of bones change and joints are destroyed by your immune system o much more common in women than men women get is 25 55 yrs old and its 3x more common with females gout arthritis caused by deposition of uric acid crystals in the joint obesity alcohol purines high food sea food this inflammation of foot Muscles 3 types 1 Skeletal muscle voluntary muscle under conscious control 2 Smooth muscle 3 Cardiac muscle 2 and 3 are involuntary muscle control these muscles work on their own ex heart muscles are connected to your bones muscles can work in opposite directions ex bicep pulls down and tricep pulls up isotonic contraction muscle tension opposing force muscle shortens isometric contraction muscle tension opposing force muscle remains at same length rather than shortening skeletal muscle structure bundles of long fibers and each fiber bundle of myofibrils muscle bundle of muscle cells fibers myofibril fibers made of TWO proteins 1 Myosin thick and 2 Actin thin protein banding pattern that s repeated sarcomere each repeated structure of banding patterns on the muscle fiber o when sarcomere shortens the muscle shortens so muscle contracts all gets tighter SEE PHOTO muscle contraction explained in detail myosin filament in resting muscle nerve impulse causes calcium release that allows myosin to bind to actin filaments myosin heads tilt toward the cente ran dpush the actin filaments using energy the myosin heads drag actin INWARD shortening sarcomere then atp binds ot myosin heads and they DETACH from actin SEE THIS IN A PHOTO ON THE SLIDES muscle motor units group of muscle fibers 1 unit because it is controlled by one nerve cell all of the fibers controlled by same nerve circuit all respond together unit happens to help body move efficiently Twitch muscles slow vs fast slow twitch muscle fibers contract slowly for a long time muscles with lots of these are RED because lots of blood supply since they need lots of OXYGEN to produce energy for CNTD contraction aerobic stead power endurance distance running walking etc fast twitch muscle fibers contract very quickly for a shorter time anaerobic explosive power fatigue easily don t use oxygen to generate energy so don t need lot of blood lighter in color infrequent but intense contraction both two diff types of fibers most muscles fast slow twitch fibers back muscles for posture Slow twitch and eye muscles Fast twitch Strength Body building exercise strengthens people through 1 myofibril hypertrophy stress damage activates actin and myosin synthesis larger fast twitch muscles damage yourself to build it up aided by anabolic hormones testosterone 2 sarcoplasmic hypotrophy body build increase fluid and energy source surrounding myofibrils 3 neural adaptation improved nerve muscle interactions so more muscle cells work together decreases natural inhibition that keeps muscles from overworking lets you control when you quit and don t you can do more overtime provides early strength gains b c requires no new protein synthesis so women use this Muscle hypertrophy generated primarily by high intensity resistance activities e g weight lifting Anabolic Steroids natural testosterone stimulates muscle growth increase body mass athletic performance men sexual reproductive disorders fluid retention severe acne women voice deepends grow facial hair enlarged clitoris and baldness NOT REVERSIBLE long term effects not really known because hasn t been around long enough but strong evidence for heart attacks stroke circulatory issues BLOOD FUNCTIONS Terms related to blood begin with hemo or hemato also spelled haemo and haemato from the Greek word haima for blood 1 Supply of oxygen to tissues bound to hemoglobin in red blood 2 Supply of