Open vs Closed Circulatory Systems Quiz

Study Notes

Open System: Fluid called hemolymph circulates throughout the body, coming into direct contact with tissues and organs. Hemolymph movement is driven by the heart, but there's no distinct separation between blood and interstitial fluid.
Closed System: Blood is confined to vessels and transported away from and back to the heart. The heart pumps blood through arteries, which carry it to capillaries for gas exchange. Veins then return blood to the heart.

5 major steps:
- Ventilation: Movement of air or water through specialized gas exchange organs (e.g., lungs, gills).
- Diffusion at respiratory surface: Oxygen moves from air/water into blood, while carbon dioxide moves from blood into air/water.
- Circulation: Transport of dissolved oxygen and carbon dioxide throughout the body by the circulatory system.
- Diffusion at tissues: Oxygen moves from blood into tissues, and carbon dioxide moves from tissues into blood.
- Cellular respiration: Cells utilize oxygen and produce carbon dioxide.

Bronchi: Narrow tubes branching off from the trachea, carrying inhaled air.
Bronchioles: Even narrower tubes branching off from bronchi.
Alveoli: Tiny air sacs in mammal lungs that increase surface area for gas exchange.
Inhalation: Diaphragm contracts, chest cavity expands, and air is drawn into the lungs.
Exhalation: Diaphragm relaxes, chest cavity contracts, and air is expelled from the lungs.

Arteries: Tough, thick-walled vessels carrying blood away from the heart under high pressure.
Capillaries: Thin-walled vessels with single cell-thick walls, allowing gas exchange between blood and tissues in capillary beds.
Veins: Thin-walled vessels returning blood to the heart.

Neuron Anatomy:
- Dendrite: Receives and converts chemical signals into electrical signals.
- Axon: Conducts electrical signals.
- Cell Body: Integrates incoming electrical signals.
Action Potential: Movement of sodium ions (Na+) out of the axon and potassium ions (K+) into the axon.
Parasympathetic Nervous System: Promotes "rest and digest" functions that conserve or restore energy.
Sympathetic Nervous System: Prepares organs for stressful situations, triggering the "fight or flight" response.

Drug abuse: Alters brain function, impacting neurotransmitters and leading to addiction and other health issues.

Ear:
- Outer Ear: Collects sound waves and funnels them to the ear canal, striking the tympanic membrane.
- Middle Ear: Transmits sound waves from the external environment to the inner ear.
- Inner Ear: Transforms vibrations for hearing and balance.
Eye:
- Cornea: Transparent sheet of connective tissue that protects the eye and refracts light.
- Iris: Pigmented round muscle regulating pupil size.
- Pupil: Hole in the center of the iris, allowing light to enter the eye.
- Lens: Curved, clear structure that focuses incoming light onto the retina.
- Retina: Light-sensitive tissue at the back of the eye containing photoreceptor cells.
Lateral Line System: Series of canals along the head and body of aquatic animals, detecting water vibrations and changes in pressure.

Sarcomere: Basic contractile unit of muscle fibers.
- Actin: Composes thin filaments.
- Myosin: Composes thick filaments.
Muscle Types:
- Smooth Muscle: Found in intestines and arteries, responsible for movement of food and regulating blood pressure.
- Cardiac Muscle: Found in the heart, pumping blood throughout the body.
- Skeletal Muscle: Attached to the skeleton, responsible for voluntary movement.
Skeletal Systems:
- Hydrostatic Skeleton: Fluid pressure within enclosed body fluids or soft tissues provides support.
- Endoskeleton: Rigid structures inside the body (e.g., bones).
- Exoskeleton: Rigid structures on the outside of the body (e.g., insect cuticle).