BIo Exam 3 Study Guide Movement and Support Endoskeleton- series of levers in the body, muscles pull on them → movement Human Skeleton - Two Divisions - Axial Skeleton - Cranium - Vertebral Skeleton - Rib Cage - Sternum - Sacrum - Coccyx - Appendicular Skeleton - Hips and Shoulders - Limbs - Vertebral (spinal) Column - 7 cervical vertebra - Atlas (yes), allows head to move up and down - Axis (no), allows head to move side to side - 12 Thoracic vertebra - Thoracic, more dense than cervical, lose mobility faster - 5 Lumbar vertebra - Lumbar, DENSE, center of gravity, compressive force - Cartilage = compressed over time ---> back probs - Sacrum - fused to form one bone - Coccyx (tail bone) Joints - Ball and socket joint - Almost 360 degree rotation - Hinge joint - Almost 180 degrees of rotation - Knees, elbows - Pivot joint - Lots of motion
17
Embed
Weebly · Web viewMyosin, thick with heads Actin, thin helix, binding sites Muscle contraction Z-lines get closer Sliding filament theory Interaction of actin and myosin depends on
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
BIo Exam 3 Study Guide
Movement and SupportEndoskeleton- series of levers in the body, muscles pull on them → movementHuman Skeleton
- Appendicular Skeleton- Hips and Shoulders- Limbs
- Vertebral (spinal) Column- 7 cervical vertebra
- Atlas (yes), allows head to move up and down- Axis (no), allows head to move side to side
- 12 Thoracic vertebra- Thoracic, more dense than cervical, lose mobility faster
- 5 Lumbar vertebra - Lumbar, DENSE, center of gravity, compressive force- Cartilage = compressed over time ---> back probs
- Sacrum - fused to form one bone- Coccyx (tail bone)
Joints- Ball and socket joint
- Almost 360 degree rotation- Hinge joint
- Almost 180 degrees of rotation- Knees, elbows
- Pivot joint- Lots of motion- Wrist, ankles, spine
- Immovable Joints- Pelvis, cranium- Move at youth so bain can grow help with birthing process- Eventually bones fuse at suture or immovable joints
Types of Bone- Flat bones
- Spongy bone only
- Shoulder, hip, sternum- Long Bones
- Dense- Handle forces (e.g. femur)- Spongy bone
- Red marrow - for making blood cells- Compact bone
- Yellow marrow - for fat storageAnatomy of a Long Bone
- Spongy bone, holes in bones = less heavy- Osteocytes = cells that make up bone- Compact bone = dense - Yellow Marrow = mostly fat
Bone is important for Ca++ regulation in the body- Calcium for muscle contraction
- Store calcium in bones- Osteoblasts (BUILD) deposit Ca++ in the bone - THICKENING AND REPAIRING
- Osteoblasts and Ca++ critical to healing of broken bones- Osteoclasts destroy bone to liberate Ca++
Interaction of Bones and Muscles- Bone → Bone = Ligament- Muscle → Bone = Tendon
Muscles- Antagonistic Pairs - muscles shorten, other muscles help pull because you can’t push
musclesThe Sarcomere
- Z line - Proteins come together- Myosin, thick with heads- Actin, thin helix, binding sites- Muscle contraction
- Z-lines get closer- Sliding filament theory- Interaction of actin and myosin depends on ATP- ATP necessary for contraction or relaxation of the muscle
Contraction of a Sarcomere 1. Impulse from a neuron (motor unit) → 2. Change in muscle cell membrane → 3. Calcium released into muscle cell (sarcoplasmic reticulum)4. Ca++ causes troponin + tropomyosin to move off the actin binding sites5. ATP attaches to myosin head → let go of actin binding sites6. ATP hydrolyzes + gives energy to myosin heads → 7. Shape change8. Myosin heads attach to actin binding sites
9. Shape change “POWER STROKE” pulls on actin10. Actin slides, moves Z lines closer together = CONTRACTION OF A SARCOMERE- Strength of contraction depends on number of motor units (neurons) activated and
number of sarcomeres activated- Not enough calcium, muscle won’t retract - Impulses from motor units increase in frequency and numbers to recruit more
sarcomeres - Too frequent = sustained (tetanic) contraction = no time to
relax → tetanus
NeuronsOrganization of the Nervous System
- 2 anatomical divisions- Central nervous system- Brain, spinal cord, process info- Peripheral nervous system- Deliver info to and from central
- 2 functional divisions- Sensory input- Collecting info- Motor output- Deliver info for action
- Somatic nervous system- Autonomic nervous system
- Parasympathetic- Calming, rest, digestion- Sympathetic- Fight or flight response
Components of Nervous System- Sensory neurons
- Collect info- Eyesight, skin, hearing
- Interneurons- Process info (integrate)- Brain, spinal cord
- Motor neurons- Action- Muscles that you can physically move
Components of a Neuron- ALWAYS travels in same direction- Dendrites- Receive info- Nerve cell body- Process info- Axon- Deliver info for action- Synaptic Knobs- Communicate with next cell
- Neurotransmitter- chemicals of communicationMyelin Aids Conduction
- Myelin sheath = fat layer- Keep signal in the axon → faster- Jump over nodes of ranvier
- Stimulus → change in membrane → opens port and positive charges- Rest between firing = refractory period- Action potential is ALL OR NOTHING (hit -40 = action potential)- Control is by NUMBER of neurons firing or SPEED of firing
Synapse is key for neuron to neuron communication- Electrical synapse
- Rapid, one-to-one passing of an impulse- Really close together, pass action potential
- Chemical synapse- Uses neurotransmitter- Can recruit more neurons- Modulation of speed
Chemical Synapse- Common Neurotransmitters:
- Serotonin- well being, inhibitory- Dopamine- motor control, inhibitory- Norepinephrine- fight/flight, excitatory- Acetylcholine- motor neurons, excitatory- Anandamide- cannabinoid receptors
Modes of Drug Action- Agonist
- Increase effectiveness of neurotransmitter- Mimic - Inhibit breakdown - Inhibit reuptake (leave in synaptic gap)
- Artery- ALWAYS AWAY from heart- Under pressure- High velocity- Lots of muscle
- Arteriole- Smaller arteries- Under pressure- Higher velocity- Thinner- Resistance
- Capillary- Business- Exchange between blood and tissues- Walls = 1 cell thick- Low pressure
- Venule- Low pressure- Low velocity- Valves- Rely on skeletal muscle to get blood back to the heart
- Vein- ALWAYS GO to heart- Large returning vessels- Have valves
Blood Pressure- Systolic (contraction of heart)- Diastolic (relaxation of heart)- Usually 120/80
Cardiac Control- Heart Rhythm- Heart muscle can initiate its own contraction- Electrical impulses from nervous system alter rate of contraction- SA Node = regulatory center
Sinoatrial node = pacemaker of heart- SA → AV → Bundle of His → Purkinje Fibers
ECG (Electronic Cardiogram)- P Wave
- Atria depolarize → Contract- QRS Complex
- Ventricles depolarize → spike → contract- T Wave