Please enable JavaScript.
Coggle requires JavaScript to display documents.
Ch 44 Ch45 - Coggle Diagram
Ch 44 Ch45
Hormones-Endocrine system
Hormone classes
Polypeptides:
Hormones made of chains of amino acids that bind to receptors on the cell surface to trigger a response.
Amines:
Hormones derived from single amino acids (usually tyrosine or tryptophan) that act as chemical messengers in the body.
Steroids:
Lipid-based hormones made from cholesterol that can pass through cell membranes and usually affect gene activity inside cells.
Types of chemicals
Prostaglandins:
Lipid-based signaling molecules that act locally in tissues to control processes like inflammation, pain, blood flow, and smooth muscle contraction.
Cytokines:
Small proteins released by immune cells that help regulate immune responses, inflammation, and communication between cells during infection or injury.
Hormones:
Chemical messengers produced by endocrine glands that travel through the bloodstream to regulate activities of distant target cells or organs.
Neurotransmitters:
Chemical messengers released by neurons that transmit signals across a synapse to another nerve cell, muscle cell, or gland cell.
Communication pathways
Autocrine: Referring to cells that secrete hormones or other signaling molecules that affect themselves.
Neuroendocrine: Pertaining to the interaction between the nervous system and the endocrine system, where nerve cells release hormones into the blood.
Paracrine: Referring to cells that secrete hormones or other signaling molecules that affect nearby cells.
Endocrine: Relating to glands that secrete hormones directly into the blood or lymph.
Receptor mechanisms
Lipid-soluble:
The way lipid-soluble hormones work by passing through the cell membrane and binding to receptors inside the cell to directly affect gene activity.
Regulation:
The process of controlling or adjusting body functions to maintain stable internal conditions (homeostasis).
Water-soluble:
The way water-soluble hormones work by binding to receptors on the cell membrane and triggering signals inside the cell without entering it.
Major Endocrine Glands
Thyroid: Anterior neck, below larynx around trachea.
Thyroxine (T₄) & Triiodothyronine (T₃): increase metabolic rate, growth, and development
Calcitonin: lowers blood calcium levels by promoting calcium storage in bones
Parathyroid: Small glands on posterior surface of thyroid.
Parathyroid Hormone (PTH): raises blood calcium levels by increasing bone breakdown and kidney calcium reabsorption
Pituitary Gland: Front portion of pituitary; located in sphenoid bone below hypothalamus.
Adrenocorticotropic Hormone (ACTH): stimulates adrenal cortex to release cortisol
Follicle-Stimulating Hormone (FSH): sperm production in males; follicle development in females
Thyroid-Stimulating Hormone (TSH): stimulates thyroid gland to release thyroid hormones
Luteinizing Hormone (LH): testosterone production in males; ovulation and estrogen/progesterone secretion in females
Growth Hormone (GH): stimulates body growth, protein synthesis, and metabolism
Prolactin (PRL): stimulates milk production
Adrenal gland: On top of the kidney
Cortex: on top of the kidney
Cortisol (glucocorticoids): stress response, increases blood glucose
Aldosterone (mineralocorticoid): regulates sodium, potassium, and blood pressure
Androgens: contribute to secondary sex characteristics
Medulla: middle of the adrenal gland
Norepinephrine: increases alertness and blood pressure
Epinephrine (adrenaline): fight-or-flight response; increases heart rate and blood glucose
Hypothalamus: Inferior medial area of the brain; links nervous system and endocrine system.
Growth hormone-releasing hormone (GHRH): stimulates growth hormone (GH) release from anterior pituitary
Growth hormone-inhibiting hormone (GHIH / somatostatin): inhibits GH release
Thyrotropin-releasing hormone (TRH): stimulates TSH release
Corticotropin-releasing hormone (CRH): stimulates ACTH release
Gonadotropin-releasing hormone (GnRH): stimulates FSH and LH release
Prolactin-releasing hormone (PRH): stimulates prolactin release
Prolactin-inhibiting hormone (PIH / dopamine): inhibits prolactin relea
Pancreas: behind the stomach, both endocrine and exocrine functions.
Insulin: lowers blood glucose by promoting uptake into cells
Glucagon: raises blood glucose by stimulating glycogen breakdown
Gonads: Pelvic cavity
Ovaries (female): pelvic cavity
Estrogen: female secondary sex characteristics and reproductive cycle regulation
Progesterone: prepares and maintains uterus for pregnancy
Testes (male): In the scrotum
Testosterone: sperm production and male secondary sex characteristics
Pineal: Deep in brain between hemispheres.
Melatonin: regulates sleep–wake cycles (circadian rhythm)
Thymus: Upper chest behind sternum.
Thymosin: promotes maturation of T-lymphocytes (immune function)
Osmoregulation and Filtration
Key concepts
Osmosis: Definition: The diffusion of water across a selectively permeable membrane from low solute concentration to high solute concentration.
Selectively permeable membrane
Definition: A membrane that allows some substances to pass through but not others.
Solute concentration: Definition: The amount of dissolved substance in a solution.
Osmoconformer
Definition: An animal whose internal osmolarity changes with the surrounding environment.
Osmoregulator
Definition: An animal that controls its internal water and salt balance, keeping it stable.
Diffusion
The movement of molecules from an area where they are more concentrated to an area where they are less concentrated.
Passive transport: Definition: The movement of substances across a cell membrane without using energy (ATP).
High to low concentration: Definition: Movement of particles from an area with more particles to an area with fewer particles.
Nitrogenous wastes Definition: Waste products containing nitrogen that come from breaking down proteins and nucleic acids.
Urea
Definition: A less toxic nitrogenous waste formed in the liver from ammonia.
Uric acid
Definition: A nitrogenous waste that is mostly insoluble in water and excreted as a paste.
Ammonia
Definition: A highly toxic nitrogenous waste that requires lots of water to eliminate.
Nephron
Definition: The functional unit of the kidney that filters blood and forms urine.
Glomerulus
Definition: A ball of capillaries in the nephron where blood filtration begins.
Bowman’s capsule
Definition: A cup-shaped structure that surrounds the glomerulus and collects filtered fluid.
Proximal tubule
Definition: The first tubule segment of the nephron where most reabsorption occurs.
Loop of Henle
Definition: A U-shaped part of the nephron that helps concentrate urine.
Distal tubule
Definition: The tubule segment after the loop of Henle that fine-tunes ion balance.
Collecting duct
Definition: The final part of the nephron that carries urine to the renal pelvis and adjusts water reabsorption.
Hormonal Regulation
ADH (Antidiuretic Hormone)
Definition: A hormone that increases water reabsorption in the kidneys, reducing urine output.
RAAS (Renin-Angiotensin-Aldosterone System)
Definition: A hormone system that regulates blood pressure and blood volume.