Skip to main content
Back

General Biology: Animal Physiology and Immunity

Control buttons has been changed to "navigation" mode.
1/29
  • Hypothalamus role in thermoregulation
    The hypothalamus acts as a biological thermostat by detecting body temperature changes and activating responses to maintain a set point of ~36–38°C.
  • Negative feedback in thermoregulation
    Deviations from the set point trigger responses that reverse the change to restore internal temperature homeostasis.
  • Response to increased body temperature
    Sweat glands secrete sweat for evaporative cooling; skin blood vessels dilate (vasodilation) to increase heat loss via radiation and convection.
  • Response to decreased body temperature
    Skin blood vessels constrict (vasoconstriction) to reduce heat loss; skeletal muscles shiver to increase metabolic heat production.
  • Fever as a thermoregulatory adjustment
    Infection raises hypothalamic set point; body triggers heat production (shivering) and heat conservation (vasoconstriction) to reach new set point.
  • Osmolarity definition
    Total solute concentration in a solution, measured in mol/L.
  • Water movement in osmosis
    Water moves from hypoosmotic (lower solute) to hyperosmotic (higher solute) solutions.
  • Osmoregulators vs osmoconformers
    Osmoregulators actively regulate internal osmolarity; osmoconformers match internal osmolarity to the environment.
  • Marine fish osmoregulation adaptations
    Drink seawater, excrete excess salts via gills and kidneys, produce small amounts of concentrated urine to conserve water.
  • Freshwater fish osmoregulation adaptations
    Do not drink water, excrete large volumes of dilute urine, actively uptake ions through gills and food.
  • Types of nitrogenous waste
    Ammonia (highly toxic, aquatic animals), urea (moderate toxicity, mammals/amphibians), uric acid (low toxicity, birds/reptiles).
  • Four main steps of excretion
    Filtration (blood pressure forces fluid out), reabsorption (useful substances returned), secretion (wastes added), excretion (urine leaves body).
  • Nephron functional units
    Includes glomerulus, Bowman’s capsule, proximal tubule, Loop of Henle, distal tubule, and collecting duct for urine formation.
  • Digestive system four stages
    Ingestion, digestion (mechanical and chemical), absorption, and elimination.
  • Difference between gastrovascular cavity and alimentary canal
    Gastrovascular cavity has one opening and lower efficiency; alimentary canal has two openings and allows one-way food flow with specialization.
  • Functions of stomach gastric juice components
    HCl denatures proteins and kills bacteria; pepsin breaks proteins into polypeptides; mucus protects stomach lining.
  • Small intestine adaptations for absorption
    Circular folds, villi, and microvilli increase surface area to maximize nutrient absorption.
  • Role of liver in digestion
    Produces bile to emulsify fats, regulates nutrients, and detoxifies substances.
  • Dental adaptations in carnivores
    Large sharp incisors and canines for cutting and tearing; sharp premolars/molars for slicing flesh.
  • Dental adaptations in herbivores
    Incisors for cutting plants, reduced canines, broad flat molars for grinding cellulose-rich plant tissue.
  • Mutualistic gut microbiome benefits
    Microbes produce vitamins, help immune development, and prevent pathogen colonization.
  • Energy sources animals require
    Chemical energy (carbohydrates, lipids, proteins), organic building blocks, and essential nutrients.
  • Hormonal control of digestion
    Gastrin stimulates stomach acid; secretin triggers bicarbonate release; CCK stimulates enzyme and bile release.
  • Innate immunity key features
    Rapid, generalized defense recognizing common pathogen patterns using barriers, phagocytes, antimicrobial peptides, and inflammation.
  • Adaptive immunity key features
    Highly specific, slower response with memory; mediated by B cells (antibodies) and T cells (cell-mediated immunity).
  • Role of helper T cells
    Coordinate adaptive immunity by activating B cells and cytotoxic T cells via cytokine secretion.
  • Clonal selection in adaptive immunity
    Only lymphocytes with receptors matching an antigen are activated, proliferate, and differentiate into effector and memory cells.
  • Difference between active and passive immunity
    Active immunity is produced by the individual's immune response and is long-lasting; passive immunity is transfer of antibodies and short-term.
  • Endocrine vs nervous system signaling
    Endocrine uses hormones for slow, widespread, long-lasting effects; nervous system uses electrical signals for fast, targeted, short-term effects.