Circulatory System Flashcards
Function of a transportation system
Keeps the body in a state of general physical well being by:
1. Delivering oxygen and nutrients to every cell of the body and removing waste carbon dioxide
2. Serving as a pathway from one part of the body to another for disease fighting agents, hormones, and other chemical messengers
3. Controlling body temperature in warm blooded animals
4. Being an essential link among the cells and organs within the body and between individual cells and the environment
Vascular System
A system of fluid tissue that plays a role in transporting nutrients and other materials to the cells of the organism
Circulatory System
A vascular system in which the progress of fluid is controlled by muscle movements so that it follows a specific pattern.
In higher animals, vascular fluid is pumped by the action of a heart.
Open Circulatory System
Blood is pumped into body cavities (not vessels), where it directly bathes the cells.
It is taken back to the heart through open-ended pores.
Closed Circulatory System
Blood is pumped through vessels that are separate from the intestitial fluid (fluid between parts of tissue) of the body
Amoeba
Self-sufficient
Uses cell surface as a point of exchange - diffusion/active transport across cell membrane
Distributed to organelles by streaming/flowing of cytoplasm
Paramecium
Single-celled protozoan
Digests nutrients that pass through a vacuole to reach all parts of the cell
Sponges (Porifera) and Rotifers (Rotifera)
Simplest animals
Diffusion, no circulatory system
Planarian (flatworm)
Diffusion through body wall
Digestive/waste cavities branch to reach cells
Hydra
Tubular
Diffusion
Grasshopper
Open circulatory system
Tubular heart-like structure pumps fluid (haemolymph) through aorta (only vessel) to body cavity (subdivided into sinuses)
Earthworm
Closed circulatory system
Dorsal (carry blood to front) and ventrical (carry blood to back) vessels connected by aortic arches that pump blood to tissues
Fish
Closed circulatory system
Gill circulation: atrium gets blood from body, ventricle pumps to gills for re-oxygenation
Blood continues to the rest of the body, then back to atrium: systemic circulation
Unidirectional oxygenated flow through two-chenbered heart
Limited rate of O2 delivery and lower metabolic capacity, as blood pressure is lost in capillaries
Frog
Closed circulatory system
Incomplete double circulation: right atrium - blood from body, left atrium - blood from lungs, mix in ventricle and are pumped to the body and lungs
Bidirectional flow of oxygenated and deoxygenated blood through a three-chambered heart
Chicken (and Human)
Closed circulatory system
Complete double circulation
Bidirectional blood flow of oxygenated and deoxygenated blood through a four-chambered heart
Arteries
Thick, elastic, and muscular tissue
Under high pressure
Carry oxygenated blood away from the heart
(Exception - pulmonary artery)
Arterioles
Smaller arteries (branching)
Carry oxygenated blood
Capillaries
Smallest blood vessels
Large in number - division of pressure
Small diameter, single layer of epithelial cells
Site of gas exchange
Veins
Thinner, less elastic, muscular
Slower circulation
Contain valves to prevent backflow of blood
Carry deoxygenated blood to the heart
(Exception - pulmonary vein)
Venules
Smaller veins
Carry deoxygenated blood
Subsystems
1) Pulmonary circuit
2) Systemic circulation
3) Cardiac circuit
Pulmonary circuit
The system of vessels that carries waste carbon dioxide to the lungs and picks up fresh oxygen
Systemic circuit
The system of vessels that carries the blood from the heart to all other body systems and organs
Cardiac circuit
The system of specialized coronary vessels that meet the energy and nutrient needs of the system
Lymphatic
Fine thin-walled tubes leading to larger ducts responsible for collecting fluids that are lost or diffused during passage so that homeostasis (steady state) can be maintained
How much blood does an average human have?
5 litres
male - 80 mLfor every kg of body mass
female - 65 mL for every kg of body mass