Human Anatomy A Speed Through

1. Human AnatomyA Speed Through

2. Urinary System • Once we have ingested the proteins, our body breaks them down into amino acids in the digestive system which are absorbed and circulated throughout the body in the blood. • Use of Amino Acids 1. To build new proteins 2. Help regulate the pH of the blood 3. As a source of energy in cell respiration

4. Using an amino acid as a source of energy causes the generation of ammonia, which is poisonous. • To get rid of ammonia, our body converts it to urea, which is removed by our excretory system making urine.

6. Urea leaves the cell and enters the blood stream. The blood reaches the kidneys and is filtered by a structure called the nephron. • Nephron takes almost all of the liquid out of the blood and passes it through a system of tubes that reabsorbs all the important good stuff (sugars, water, salt) and leaves the bad stuff (urea) behind.

8. This is where the body also balances (homeostasis) the level of water and salt in your body. • If you have too much water, your urine will be lighter. • If you have too little water, the urea will be more concentrated and your urine will be darker. This is regulated by a hormone called Anti-diuretic Hormone, or ADH. When you don’t have enough water in your blood, your hypothalamus in your brain senses this and releases ADH. This causes your kidneys to reabsorb more water making your urine darker. Certain chemicals called diuretics (such a caffeine and alcohol) have the opposite effect and make you absorb less waterPEE more!

9. Nervous System • Purpose: Inputsensory information and outputbody regulation Ex: Senses, movement, thought, perception • Parts:CNS – central nervous system - regulate body • Ex: Brain and Spinal CordPNS – peripheral nervous system - communicate Ex: Nerves that extend from the spinal cord to the rest of the body

11. Nervous system basic unit = neuron nerve cell • Neuron Parts: • Cell body – houses nucleus • Dendrites – receive signals • Axon – transfers signals to effector cellsEffector Cells: other nerve cells, muscle cells, organs

13. Transmission of Nerve Signal • Resting Nerve: • Nerve cell maintains a balance of sodium and potassium ions across its cell membrane at a ratio of 3 sodium ions on the outside of the nerve cell to 2 potassium ions on the inside of the nerve cell = Resting Potential

15. Stimulation: • When a nerve is stimulated enough (heat, touch, cold, light, pain) it reaches the Threshold Potential – triggers the nerve cell • Sodium ions rush into the cell and potassium ions rush out Action Potential = causes the next section of the nerve cell to do the same thing – like The Wave – transferring the signal down the nerve

18. Undershoot/Reestablishing the Resting Potential: Sodium ions must be actively transported out of the cell and Potassium ions into the cell • At this point the nerve can’t be restimulated until the resting potential is reestablished (about 2 milliseconds) • ANALOGY: Dominoes • Setting up the dominoes is establishing the resting potential • Starting the domino chain is the stimulus • The action potential is the line of dominoes falling • The time it takes to set the dominoes back up is the Undershoot time

19. Nerve Signal Transmission • Once the nerve signal gets to the end of the nerve cell it must be transmitted to the next nerve cell or effector cell and therefore must cross the SYNAPSE , the gap between the two cells • The action potential stimulated the nerve cell to release chemicals called neurotransmitters which cross the synapse, bind to the next cell, and stimulate the action potential in the next cell

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21. Endocrine System • System of organs and glands that secrete hormones to regulate our body functions (Homeostasis) • Endocrine Glands: Hypothalamus Pituitary Gland Pineal Gland Thyroid & Parathyroid Adrenal Gland Pancreas Ovaries Testes

23. Hypothalamus & Pituitary Gland • Controls the pituitary gland, which secretes MANY hormones for regulating the body • Examples: Antidiuretic hormone – blood water/salt balance Growth hormone

25. Pineal Gland – secretes melatonin – sleep cycle

26. Thyroid and Parathyroid: • Control metabolism and blood calcium levels

27. Adrenal Gland • Secretes Adrenaline – Fight or Flight Response – increases blood and energy flow to your muscles • Secretes Corticosteroids – raise energy and blood pressure and suppress allergic reactions

28. Pancreas: Controls blood sugar levelsInsulin – lowers blood sugar Glucagon – raises blood sugar • These two work antagonistically to balance the blood glucose levels around 90 mg/100 mL of blood

29. Ovaries and Testes: • Responsible for sexual maturation and regulation of gamete development • Ovaries  Estrogen and Progesterone • Testes  Testosterone

30. Immune System • Body’s Defensive System • General Immunity: • Skin • Mucous • Sweat • Fevers • Inflammatory Response – histamine release causes increase in blood flow to an area – pressure etc. Exaggerated response = allergies • Macrophages – white blood cells that eat invaders

31. Antibodies – proteins in the body that recognize foreign invaders and bind to their outer proteins

32. Specific Response: • Specific White Blood Cells: • B Cells – attack free floating pathogens in the blood (bacteria and viruses) • T Cells – attack cells that have been infected by viruses and destroy them

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35. B cells and T cells that have been activated by their specific pathogen form Memory Cells to more readily identify the pathogen should reinfection occur - purpose of vaccines is to introduce a dead or weakened pathogen so the immune system can make the memory cells