Presentation on theme: "Homeostasis and Endocrine Signaling. Tissues Figure 32.2 4 major types: Epithelial – found on outside of the body and lining organs and cavities. Muscle."— Presentation transcript:
Homeostasis and Endocrine Signaling
Tissues Figure major types: Epithelial – found on outside of the body and lining organs and cavities. Muscle – 3 types Cardiac – heart tissue, involuntary Smooth – involuntary actions in body, organs, blood vessels Skeletal – muscle that moves, attaches to bone, voluntary
Nervous tissue – the neuron, sends impulses, communication Glia cells are nerve helping cells to the neurons Connective tissue – diverse group of tissues scattered throughout body and extracellular matrix Bone – calcified hard matrix Blood – liquid matrix Cartilage – ear, nose, gel like matrix Dense fibrous – tendons and ligaments Adipose - fat Areolar – loose fibrous connecting tissue
Regulator or Conformer? Animals that are regulators uses internal mechanisms to control internal change – endothermic, homeothermic, warm blooded Animals that are conformers – internal condition changes in accordance with external changes, ectothermic, cold blooded Homeostasis – maintenance of a constant internal balance examples,- body temp, blood glucose levels… Negative feedback – when body is out of homeostasis and it is brought back. Positive feedback – when body is brought out of homeostasis purposely for a short period of time, childbirth and oxytocin
Thermoregulation (heat) Figure 32.3
Figure 32.4 Sensor/ control center: Thermostat turns heater off. Sensor/ control center: Thermostat turns heater on. Stimulus: Room temperature increases. Stimulus: Room temperature decreases. Room temperature increases. Room temperature decreases. Set point: Room temperature at 20 C Response: Heating stops. Response: Heating starts.
Endocrine system Endocrine system – communication via hormones that are released by endocrine glands into the blood stream. Hormones – chemical messengers Exocrine glands – figure Exocrine glands – integumentary system, release product to cavity or outside the body, sweat. Nervous system – rapid communication using neurons and nerve impulses All run by Stimulus/Response mechanism
Figure 32.11a Pancreas Insulin Glucagon Testes (in males) Androgens Parathyroid glands Parathyroid hormone (PTH) Ovaries (in females) Estrogens Progestins Thyroid gland Thyroid hormone (T 3 and T 4 ) Calcitonin Pineal gland Melatonin Major Endocrine Glands and Their Hormones Hypothalamus Pituitary gland Anterior pituitary Posterior pituitary Oxytocin Vasopressin (antidiuretic hormone, ADH) Adrenal glands (atop kidneys) Adrenal medulla Epinephrine and norepinephrine Adrenal cortex Glucocorticoids Mineralocorticoids
Figure 32.8 Sensor/control center: Thermostat in hypothalamus Stimulus: Decreased body temperature Body temperature increases. Body temperature decreases. Homeostasis: Internal body temperature of approximately 36–38 C Response: Blood vessels in skin dilate. Response: Shivering Sensor/control center: Thermostat in hypothalamus Response: Blood vessels in skin constrict. Stimulus: Increased body temperature Response: Sweat
Figure 32.9 Cell body of neuron Response Hormone Nerve impulse Signal travels everywhere. Signal travels to a specific location. Response Stimulus Nerve impulse Blood vessel Endocrine cell (a) Signaling by hormones Axons Axon (b) Signaling by neurons
Osmoregulation (fluids) How animals control solute concentrations in the interstitial fluid and balance water gain and loss Excretory system – releasing of nitrogenous and metabolic waste products (kidney) Osmoconformer – being isoosmotic with its surroundings, marine animals Osmoregulator – to control internal osmolarity independent of the environment. Allows animals to live in freshwater/terrestrial habitats.
Nitrogenous wastes in animals 32.16
Figure Most aquatic animals, including most bony fishes ProteinsNucleic acids Amino acids Nitrogenous bases Amino groups Mammals, most amphibians, sharks, some bony fishes Many reptiles (including birds), insects, land snails Ammonia Urea Uric acid
Figure 32.16a Most aquatic animals, including most bony fishes Mammals, most amphibians, sharks, some bony fishes Many reptiles (including birds), insects, land snails Ammonia Urea Uric acid
Figure 32.19bc Nephron Organization Collecting duct Branch of renal vein Vasa recta Efferent arteriole from glomerulus Distal tubule Afferent arteriole from renal artery Glomerulus Bowman’s capsule Proximal tubule Peritubular capillaries Descending limb Ascending limb Loop of Henle
Figure Filtrate OUTER MEDULLA H2OH2O Salts (NaCI and others) HCO 3 − Glucose, amino acids HH Some drugs Passive transport Active transport Key INNER MEDULLA CORTEX Descending limb of loop of Henle H2OH2O Interstitial fluid NH 3 HH Nutrients HCO 3 − KK NaCI Proximal tubule H2OH2O Thick segment of ascending limb HH Urea HCO 3 − KK NaCI Distal tubule H2OH2O Thin segment of ascending limb NaCI H2OH2O Collecting duct Urea
Adaptations Based on where you live, there are adaptations to the kidney Hyperosmotic urine (dessert animals) – long loops of Henle that extend deep into the medulla Birds – shorter loop of Henle, les concentrated urine compared to mammals – uric acid is product to help conserve water.
Homeostatic regulation of kidney antidiruretic hormone
Figure Distal tubule H 2 O reabsorption STIMULUS: Increase in blood osmolarity Drinking of fluids Increased permeability Osmoreceptors trigger release of ADH. Thirst ADH Collecting duct Homeostasis