RATED A+
✔✔Diffusion - ✔✔Substances like oxygen and carbon dioxide move from high to low
concentration.
✔✔Filtration - ✔✔Water and small solutes are pushed out of the capillaries due to
pressure.
✔✔Reabsorption - ✔✔Larger molecules (like proteins) draw water back into the
capillaries due to osmotic pressure.
✔✔Importance of bulk flow - ✔✔It helps move nutrients, gases, and wastes between the
blood and tissues.
✔✔Hydrostatic pressure (HP) - ✔✔Pushes fluid out of capillaries.
✔✔Osmotic pressure (OP) - ✔✔Pulls fluid back into capillaries.
✔✔Venous return factors - ✔✔Skeletal muscle pump: Muscle contractions help push
blood in veins toward the heart. Respiratory pump: Breathing creates pressure changes
that help move blood toward the heart. Venous valves: Prevent backflow and ensure
blood moves in the right direction.
✔✔Systemic vascular resistance factors - ✔✔Vessel diameter: Smaller diameter =
higher resistance. Blood viscosity: Thicker blood = higher resistance. Total vessel
length: Longer vessels = higher resistance.
✔✔Arterial blood pressure - ✔✔Influenced by heart output and the resistance of blood
vessels.
✔✔Renin-angiotensin - ✔✔Raises blood pressure by constricting blood vessels and
increasing fluid retention.
✔✔Aldosterone - ✔✔Increases blood pressure by promoting sodium and water
retention.
✔✔Epinephrine & Norepinephrine - ✔✔Raise blood pressure by constricting blood
vessels and increasing heart rate.
✔✔ADH (Antidiuretic hormone) - ✔✔Raises blood pressure by promoting water
retention.
, ✔✔ANP (Atrial Natriuretic Peptide) - ✔✔Lowers blood pressure by promoting sodium
and water excretion.
✔✔Hypovolemic shock - ✔✔Due to low blood volume (e.g., blood loss).
✔✔Cardiogenic shock - ✔✔Due to the heart's inability to pump effectively.
✔✔Obstructive shock - ✔✔Due to a blockage in blood flow (e.g., pulmonary embolism).
✔✔Distributive shock - ✔✔Due to widespread vasodilation (e.g., sepsis or anaphylaxis).
✔✔First line of defense - ✔✔Includes physical barriers: Skin, mucous membranes;
chemical barriers: Stomach acid, enzymes in saliva; mechanical barriers: Coughing,
sneezing.
✔✔Second line of defense - ✔✔Includes phagocytes: Engulf and digest pathogens
(e.g., neutrophils, macrophages); inflammation: Helps isolate pathogens; fever: Raises
body temperature to inhibit pathogen growth; antimicrobial proteins: Like interferons,
which prevent viral replication.
✔✔Chemotaxis - ✔✔Phagocytes are attracted to the site of infection by chemical
signals.
✔✔Adherence - ✔✔Phagocyte binds to the pathogen.
✔✔Ingestion - ✔✔The pathogen is engulfed into a vesicle called a phagosome.
✔✔Digestion - ✔✔The phagosome fuses with a lysosome, and enzymes break down
the pathogen.
✔✔Exocytosis - ✔✔The waste material is expelled from the phagocyte.
✔✔Symptoms of inflammation - ✔✔Redness, heat, swelling, pain, and loss of function.
✔✔Stages of inflammation - ✔✔Vasodilation: Blood vessels expand to increase blood
flow to the area; Increased permeability: Blood vessels become more permeable to
allow immune cells to pass through; Phagocytosis: Immune cells clear pathogens and
debris; Tissue repair: Healing begins once the infection is controlled.
✔✔Adaptive (specific) immunity - ✔✔Immunity that targets specific pathogens through
specialized cells (B and T cells).
✔✔Specificity - ✔✔The immune system targets specific antigens (unique molecules) on
pathogens.