Human Biology Terms PDF

Terms to Know (with Short Descriptions) ​ Alveoli - Tiny air sacs in the lungs where gas exchange occurs. ​ Digestive system - The body system that breaks down food, absorbs nutrients, and removes waste. ​ Larynx - The voice box; located in the throat and helps with breathing and sound...

Terms to Know (with Short Descriptions) ​ Alveoli - Tiny air sacs in the lungs where gas exchange occurs. ​ Digestive system - The body system that breaks down food, absorbs nutrients, and removes waste. ​ Larynx - The voice box; located in the throat and helps with breathing and sound production. ​ Stomach - A muscular organ that breaks down food using acids and enzymes. ​ Aorta - The largest artery in the body; carries oxygen-rich blood from the heart to the rest of the body. ​ Diastolic pressure - The pressure in arteries when the heart is at rest between beats. ​ Pulse - The rhythmic throbbing of arteries as blood is pumped by the heart. ​ Systolic pressure - The pressure in arteries when the heart contracts. ​ Arteries - Blood vessels that carry oxygen-rich blood away from the heart. ​ Diaphragm - A muscle that helps with breathing by contracting and relaxing. ​ Residual volume - The amount of air remaining in the lungs after full exhalation. ​ Thermometer - A tool used to measure body temperature. ​ Blood pressure - The force of blood against artery walls, measured in mmHg. ​ Esophagus - The tube that carries food from the mouth to the stomach. ​ Respiration rate - The number of breaths taken per minute. ​ Thermoregulation - The process of maintaining body temperature. ​ Body temperature - The measurement of the body's heat. ​ Exhalation - The process of breathing out carbon dioxide. ​ Respiratory system - The body system responsible for breathing and gas exchange. ​ Total lung capacity - The maximum volume of air the lungs can hold. ​ Bronchi - The main airways that lead from the trachea to the lungs. ​ Heart rate - The number of heartbeats per minute. ​ Respirometer/spirometer - A device used to measure lung capacity and breathing rate. ​ Trachea - The windpipe; connects the throat to the lungs. ​ Capillaries - Tiny blood vessels where gas and nutrient exchange occurs. ​ Homeostasis - The body's ability to maintain a stable internal environment. ​ Sphygmomanometer - A device used to measure blood pressure. ​ Veins - Blood vessels that carry oxygen-poor blood back to the heart. ​ Cardiovascular - Related to the heart and blood vessels. ​ Spirogram - A graph showing lung function and breathing patterns. ​ Vital capacity - The total amount of air that can be exhaled after a deep breath. ​ Circulatory system - The system that circulates blood and oxygen throughout the body. ​ Intestines - The organs that absorb nutrients and water from food and remove waste. ​ Stethoscope - A tool used to listen to heartbeats and lung sounds. ​ Vital signs - Key indicators of health, including heart rate, blood pressure, body temperature, and respiration rate. Topics to Know Body Systems Overview Digestive System ​ Main Function: Breaks down food, absorbs nutrients, and removes waste. ​ Pathway of Food: ○​ Mouth → Esophagus → Stomach → Small Intestine → Large Intestine → Anus Respiratory System ​ Main Function: Facilitates gas exchange (oxygen in, carbon dioxide out). ​ Pathway of Air: ○​ Mouth/Nose → Trachea → Bronchi → Lungs → Alveoli (gas exchange) → Back out ​ Lung Protection: ○​ Cilia - Tiny hair-like structures that trap dust and particles. ○​ Mucus - Sticky substance that captures harmful particles and bacteria. Circulatory/Cardiovascular System ​ Main Function: Transports oxygen, nutrients, and waste throughout the body. ​ How Heartbeat is Created: ○​ The sinoatrial (SA) node sends electrical signals, causing heart contractions. ​ Components of Blood: ○​ Red blood cells, white blood cells, platelets, plasma. ​ Right vs. Left Side of Heart: ○​ Right side: Pumps oxygen-poor blood to the lungs. ○​ Left side: Pumps oxygen-rich blood to the body. ​ Veins vs. Arteries: ○​ Veins: Carry oxygen-poor blood back to the heart. ○​ Arteries: Carry oxygen-rich blood away from the heart. Vital Signs The Four Main Vital Signs 1.​ Heart Rate - Measured in beats per minute (bpm) using a stethoscope or pulse check. 2.​ Blood Pressure - Measured using a sphygmomanometer; recorded as systolic/diastolic. 3.​ Body Temperature - Measured with a thermometer; normal range is around 36.1–37.2°C. 4.​ Respiration Rate - Measured in breaths per minute. How Vital Signs are Measured ​ Heart rate: Stethoscope, pulse check  ​ Blood pressure: Sphygmomanometer ​ Body temperature: Thermometer ​ Respiration rate: Observation or respirometer Recognizing Normal Ranges ​ Heart Rate: 60–100 bpm (resting adult) ​ Blood Pressure: 120/80 mmHg (normal adult) ​ Body Temperature: 36.1–37.2°C ​ Respiration Rate: 12–20 breaths per minute Blood Pressure (Systolic vs. Diastolic) ​ Systolic Pressure: The pressure when the heart contracts (top number). ​ Diastolic Pressure: The pressure when the heart relaxes (bottom number). Spirogram Interpretation ​ Shows lung function and breathing patterns. ​ Can indicate conditions like asthma or COPD. Thermoregulation - How Our Bodies Maintain Temperature ​ Cooling Down: ○​ Sweating ○​ Blood vessel dilation (vasodilation) ​ Warming Up: ○​ Shivering ○​ Blood vessel constriction (vasoconstriction) ○​ Increased metabolism