Please enable JavaScript.

Coggle requires JavaScript to display documents.

Circulation and Osmoregulation (Osmoregulation (Excretion: The process of…

- - - - Pumps blood through vessels (veins, arteries, and capillaries) to deliver oxygen, nutrients, and remove waste materials from body cells
    - - Pumps hemolymph through sinuses (cavities) that surround organs to deliver proteins and sugars to body cells
    - - Sections
        
        Atria: Chamber for receiving blood into the heart.
        
        Valves: Muscular tissue that separates chambers and prevents blood from flowing in the wrong direction. Atrioventricular valves separate the atria from the ventricles, while the semilunar valves prevent blood exiting the heart from backflowing
        
        Ventricles: Chamber that pumps blood out of the heart and into the body. In humans, there are two ventricles, one for oxygen-rich blood to enter the body, one for oxygen-poor blood to enter the lungs
        
        Aorta: Tube that carries oxygen-rich blood out of the heart and into the arteries. Has several off-shoot vessels
        
        Pulmonary Artery: Transports oxygen-poor blood to the lungs for oxygenation
        
        Nodes: Cell clusters that maintain the rhythm of the heart. The sinoatrial (SA) node sets the rate and timing of the contractions of cardiac muscles, while the atrioventricular node controls the opening of the atrioventricular valves to allow full atrial emptying before contraction
      - Tissues
        
        Cardiac Muscle: Striated muscle with intercalated disks that transmit signals between cells of the heart and promote rhythmic beating
- - - - Circulatory system with vessels that feed into open sinuses surrounding the internal organs. Circulatory fluid also serves as interstitial fluid, bathing the organs while also transferring nutrients and wastes to and from the body cells.
        
        Hemolymph: Hemocyte-containing fluid in many invertebrates, including molluscs and insects. Copper-based hemocyanin cannot transport oxygen, but delivers vital sugars and proteins to the body cells
    - - Circulatory system that keeps circulatory fluid housed in a series of vessels. The heart pumps fluid through the veins and arteries to deliver nutrients and collect waste from the cells of the body
        
        Double Circulation: Oxygen-rich and oxygen-poor blood travel through separate pathways that converge, to varying degrees, in the heart.
        
        In Birds and Mammals
        
        Blood flows through a four-chambered heart (two atria and two ventricles) that completely separates oxygen-rich and oxygen-poor blood. The right atria fills with oxygen-poor blood, which is pumped through the right ventricle to the lungs for oxygenation. Oxygen-rich blood is then delivered to the cells of the body for gas exchange and waste collection
        
        In Amphibians
        
        Blood flows through a three-chambered heart (two atria, one ventricle) where oxygen-rich and oxygen-poor blood are pumped through with slight mixing (~10% of oxygen-poor blood). The lungs are shut down underwater, making skin the primary site of gas exchange to oxygenate blood
        
        Pulmocutaneous Circuit: Network of capillaries that absorbs oxygen into the blood through both the lungs and the skin
        
        In Reptiles
        
        Blood flows through a three-chambered heart (two atria, one partially divided ventricle) to deliver oxygen to the cells of the body. In some reptiles the pulmonary and systemic circuits are connected, allowing the animal to divert blood flow to the lungs while underwater.
        
        Pulmonary Circuit: Network of capillaries that absorb oxygen into the blood through the lungs. Present in reptiles, birds, and mammals
        
        Blood: Hemoglobin-containing fluid that functions as the main circulatory fluid in many animals. Red blood cells (erythrocytes) carry oxygen to body cells and remove waste materials. White blood cells (leukocytes) aid in immune function by attacking foreign cells with antibodies.
        
        Blood Pressure: The force exerted by blood on the surrounding vessels. Represented in mm Hg
        
        Systolic Pressure: Blood pressure at the moment when the ventricles contract and push blood to the arteries. Highest point of blood pressure, with a measure of ~120 mm Hg in a healthy adult
        
        Diastolic Pressure: Blood pressure at the moment when the arteries snap back into place, pushing blood through the body. ~ 70 mm Hg
        
        Hemoglobin: Iron-containing protein responsible for oxygen absorption in blood
        
        Single Circulation: A two-chambered heart, present in bony fishes, rays, and sharks, pumps oxygen-poor blood to the gill capillaries to gather oxygen, then to the body capillaries for gas exchange. Working in a single circuit, all of the blood going through the heart is oxygen-poor.
    - - The closed circulatory system of humans and other vertebrates. Blood circulates through an extensive network of veins, arteries, and capillaries to deliver oxygen and nutrients to cells and collect waste materials.
        
        Capillaries: Microscopic vessels with thin, permeable walls for gas and nutrient exchange.
        
        Capillary Beds: Networks of capillaries that run through all of the tissues of the body, coming into close proximity with every body cell to deliver oxygen and remove waste
        
        Veins: Vessels that carry oxygen-poor blood back to the heart
        
        Venules: Vessels that form from the convergence of capillaries, and by extension converge to form veins.
        
        Arteries: Vessels that carry oxygenated blood away from the heart.
        
        Arterioles: Small vessels that branch off of arteries to deliver blood to capillaries
    - - Trachea: The windpipe. Channel by which air enters the body to travel to the lungs.
      - Bronchi: Two tubes that diverge from the trachea towards each long (singular: bronchus) Split further into finer tubes called bronchioles, similar to arteries branching into arterioles and capillaries.
      - Larynx: Upper part of the respiratory tract. Covers the glottis with the epiglottis when food is swallowed to prevent it from entering the lungs
      - Lungs: Air-filled organs, typically in the chest cavity near the heart, which take oxygen in and transfer it to the bloodstream
        
        Negative pressure breathing: Using muscle contraction to change the air pressure within the lungs relative to the outside environment
        
        Positive pressure breathing: Air is drawn through the nostrils into the oral cavity, and is then pushed down the trachea by muscular contractions. Typical of amphibians
      - Alveoli: Small air-sacs clustered in the bronchioles that take in oxygen and eject carbon dioxide. Gases diffuse through the epithelial membrane of the alveoli, with oxygen taken into the capillaries of the lungs and carbon dioxide ejected.
      - Gills: Organs present in many aquatic creatures, present as slits along the neck with membranes that absorb oxygen from the water
      - Skin: Amphibious creatures, such as frogs, can diffuse gases through permeable membranes of the skin, allowing for respiration even while underwater
      - Diaphragm: The primary muscle responsible for breathing. Contracts upon inhalation, moving down to allow air into the lungs, then relaxes on exhalation, moving up to push air out
      - Tracheal system: Present in insects, utilizes tubes that run the length of the body which take in and diffuse oxygen to the blood. Most common form of respiratory system on the planet
        
        Tracheae: Largest tubes of the internal respiratory system, Open to the outside of the body to take in oxygen
        
        Tracheole: Branching tubes that split from tracheae to deliver oxygen to body cells
        
        Air sacs: Enlarged chambers along the tracheae near organs that require significant oxygen
    - - System of vessels woven between circulatory capillaries that transports fluid called lymph taken from blood. Maintains proper fluid levels throughout the body by taking excess fluid from the blood
        
        Lymph: Interstitial fluid that functions in the transfer of lipids from the blood
        
        Lymph vessels: Vessels that transmit lymph throughout the body to maintain balance of fluid pressure. Blockage can result in swelling at the site (elephantiasis)
        
        Lymph nodes: Honeycomb-like organs filled with white blood cells that filter lymph as it travels down vessels. Produce immune cells when the body is under attack, which can result in swelling in areas such as the neck, armpit, and groin
        
        The lymphatic system has in recent years been the subject of research regarding its function in immune response
- - - - Freshwater fish: Solute ions are taken in through food and their gills, while osmotic water is gained through the skin and gills. Water is released through the excretion of dilute (solute-poor) urine to prevent salt loss
      - Marine Fish: Solute ions are taken in through food and seawater, and diffused through the permeable membranes of the gills, as well as in urine to keep internal salt levels lower than surroundings
      - Humans: Significant water is lost through urine and evaporation. The majority of this must be recovered by ingesting it as liquid, with smaller amounts ingested as food or metabolized
  - - - Urea excretion: Because of its low toxicity, urea can be stored and excreted in high concentrations. Large amounts of urea are passed through a relatively small volume of water as urine out of the body. Present in all mammals, most amphibians, as well as sharks and some bony fish
    - - Uric acid excretion: Passes through the body as a paste with minimal water absorption. Contains nitrates that diffuse into soi, making guano (uric acid rich waste) valuable as a fertilizer. Present in reptiles, birds, insects, and land snails
    - - Ammonia excretion: Animals that excrete ammonia must have access to substantial water to dilute it. Most common in aquatic species, where it is diffused across permeable membranes of the skin into the surrounding water as NH4+
    - - Protonephridia: Series of cilia-capped tubules filters waste from the interstitial fluid, which is then moved outward to be excreted as urine. Typical of Platyhelminthes (flatworms), annelids, and lancelets
      - Metanephridia: Cilia-lined tubules filter waste from the coelom, which is then processed out of the body as urine. Solutes are taken back up from urine prior to excretion as part of osmoregulation. Present in earthworms
      - Malphigian Tubules: Channels that begin in the hemolymph and extend to the digestive system. Permeates solutes into the lumen of the tubule from hemolymph, where excess is transported to the intestine. Water and solutes are reabsorbed, and the excess is excreted as solid waste (feces)
      - Excretory Organs
        
        Ureter: Duct that carries urine to the urinary bladder for storage
        
        Urinary Bladder: Sac used for storage of urine.
        
        Kidneys: Bean-shaped organ consisting of many tubules. Serves as the primary filters of nitrogenous waste in the body
        
        Nephron: Functional cells of a kidney. Each kidney contains over 1 million nephrons, which process and filter waste out of blood.
        
        Proximal tubule, Loop of Henle, and Distal tubule: Filtering section of the nephron. Blood passes through each of these sections as is being pumped. The proximal tubule and loop of henle reabsorb water, while the distal tubule reabsorbs solute ions
        
        Collecting Duct: Transport epithilia that gathers and processes the filtrate, forming urine
        
        Bowman's Capsule: Cup-shaped swelling of epithelial tissue that surrounds the glomerulus to provide insulation
        
        Peritubular capillaries: Capillaries surrounding the proximal and distal tubules, providing oxygen to the structures
        
        Glomerulus: Ball of capillaries that feed blood into the nephron
        
        Vasa Recta: Network of capillaries that surrounds the loop of henle and provides it with oxygen
        
        Urethra: Tube that excretes urine outside of the body.