Body Systems Highlights!
Nervous System
Major Structures?
Central Nervous System (CNS): Brain and Spinal Cord
Peripheral Nervous System (PNS): Nerves branching out from spinal cord
Functions: to transmit messages
Nervous System: Major Processes
Neurons: Cells of the nervous system.
Cell body-> Axon-> Dendrites
Neuron receives messages at the cell body, then it electronically carries the message down the axon to the dendrites where it triggers chemical transmitters (neurotransmitters) to send a chemical message to the next neuron.
Nervous System: Major ProcessesAction potential moves down the Axon
Diseases that affect the nervous system:
• Alzheimer's – Breakdown of brain cells and neurotransmitters, affects brain functions, memory and behavior.
• Bell's Palsy- sudden weakness or paralysis of one side of the face due to inflammation or damage of a facial nerve. Usually temporary.
• Cerebral Palsy- reduced ability to control muscles due to nervous system damage.
• Epilepsy- range of conditions, sudden recurrent episodes of seizures.
• Multiple Sclerosis (MS) - damage to the protective sheath (myelin) that surrounds nerve fibers in the brain and spinal cord.
Integumentary System
• Structures: Skin, hair, nails, glands, and nerves.
• Functions: 1) Regulate body temp, 2) Protection 3) Detect environmental changes, 4) Waste (Sweat) 5) Sunscreen 6) Storage 7) Vitamin D production
Major Processes
The basal layer contains epidermal stem cells that produce new skin cells.
Diseases of the Integumentary System
• Skin Cancers
• Eczema
• Acne
• Burns
• Etc.
Muscular System• Structure:
• Smooth: No striations• Cardiac: Heart: striated, intercalated
discs• Skeletal: Straited, multinucleated,
• Function: Movement, and stabilization.
Muscle Processes: Muscle Contraction• Steps of muscle contraction:
• Depolarization and calcium ion release• Actin and myosin cross-bridge formation• Sliding mechanism of actin and myosin
filaments• Sarcomere shortening (muscle contraction)
https://ib.bioninja.com.au/higher-level/topic-11-animal-physiology/112-movement/muscle-contraction.html
Videos: https://www.youtube.com/watch?v=Ktv-CaOt6UQ&list=PL8dPuuaLjXtOAKed_MxxWBNaPno5h3Zs8&index=22&t=0s
Or: https://www.youtube.com/watch?v=I80Xx7pA9hQ&list=PL8dPuuaLjXtOAKed_MxxWBNaPno5h3Zs8&index=23
Muscle Contraction
Diseases of the Muscular System
• Muscular Dystrophy- category of diseases that lead to a weakening of the skeletal muscles.
• Amyotrophic Lateral Sclerosis- (ALS) Progressive muscle weakening and atrophy due to the degeneration of motor neurons.
Circulatory System• Heart, Arteries, Capilaries and Veins.
• Function: To circulate oxygen, nutrients etc to your cells and to take away CO2 and waste from your cells.
• Process: know how the heart works. (in to the right atrium, to the right ventrical, to the pulmonary arteries, to the lungs. Pick up O2, back to the heart via the pulmonary veins, to the left atrium, left ventrical and then up to the aorta and out to the rest of the body!
• Diseases:• Corinary artery disease- damages the blood
vessels that supply the heart with oxygen- can lead to heart attack
• Arteriosclerosis- hardening of the blood vessel walls- can lead to build up of plaque, clots and heart problems.
Skeletal System
• Structure: Osteocytes (bone cells), compact and spongy.
• Function: See diagram
Respiratory System
Structure and Function: (diagram)
Process: the diaphragm pulls the lungs down- causing decreased air pressure in the lungs, this leads to air going into the lungs, then the diaphragm pushes up squeezing the lungs- leading to air being forced out of the lungs. That is how you breath.
Diseases:
Asthma constricts your bronchai leading to reduced air flow.
And COPD (chronic obstructive pulmonary disease).
Digestive/Excretory System
• Structure & Function: To take in nutrients and expell waste.
• Process: process of digestion (salavary glands, stomach acid, bile) absorbtion (intestines)
• Diseases:• Crohn's
• Celiacs
Endocrine System
• Structure: The glands, and hormones.
• Function: Sending chemical messages to regulate your body.
How does it work?• Positive and negative
feedback loops.
• Cell receptors (internal and external).
Diseases of the Endocrine System• Goiter- insufficient iodine
• Thyroid disease (hypo- too little and hyper- too much) affects metabolism.