Unit 1 Lesson 3 The Circulatory and Respiratory Systems Copyright © Houghton Mifflin Harcourt Publishing Company 1

Go with the Flow! What is the circulatory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems Go with the Flow! What is the circulatory system? The circulatory system includes both the cardiovascular system and the lymphatic system. Both systems move fluids around the body and protect it from disease. Copyright © Houghton Mifflin Harcourt Publishing Company 2

What is the circulatory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What is the circulatory system? The cardiovascular system is your heart, blood, and blood vessels. Blood is the fluid that carries gases, nutrients, and wastes through the body. The cardiovascular system is a closed-loop system. Copyright © Houghton Mifflin Harcourt Publishing Company 3

What is the circulatory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What is the circulatory system? The lymphatic system is a group of organs and tissues that collect fluid that leaks from blood and returns it to the blood. Lymph is the leaked fluid. The lymphatic system is an open-loop system. It can move in and out of blood vessels. Copyright © Houghton Mifflin Harcourt Publishing Company 4

How do the systems work together? Unit 1 Lesson 3 The Circulatory and Respiratory Systems How do the systems work together? As the heart pumps, fluid leaks out through capillaries, or the tiniest blood vessels. Most of this fluid is reabsorbed by the capillaries. Lymph capillaries absorb the extra fluid that contains particles such as dead cells and pathogens. Copyright © Houghton Mifflin Harcourt Publishing Company 5

How do the systems work together? Unit 1 Lesson 3 The Circulatory and Respiratory Systems How do the systems work together? Lymph is returned to the cardiovascular system when it drains into blood vessels in the base of the neck. White blood cells, which fight pathogens, mature in the lymphatic system. Copyright © Houghton Mifflin Harcourt Publishing Company 6

Node Doubt! What are the parts of the lymphatic system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems Node Doubt! What are the parts of the lymphatic system? Lymph nodes are small, bean-shaped organs that remove pathogens and dead cells from lymph. Infection-fighting white blood cells are found in lymph nodes. Lymph nodes are concentrated in the armpits, neck, and groin. Swelling in lymph nodes can be a sign of infection. Copyright © Houghton Mifflin Harcourt Publishing Company 7

What are the parts of the lymphatic system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are the parts of the lymphatic system? Lymph vessels are the thin-walled vessels with valves that carry lymph back to lymph nodes. Bone marrow is the soft tissue inside bones where blood cells are produced. Tonsils are small organs at the back of the throat that help defend the body against infection. An infection of the tonsils is called tonsillitis. Copyright © Houghton Mifflin Harcourt Publishing Company 8

What are the parts of the lymphatic system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are the parts of the lymphatic system? The thymus is an organ in the chest where some white blood cells go to finish developing. The spleen is the largest lymphatic organ. It stores white blood cells and allows them to mature. As blood flows through the spleen, white blood cells attack or mark pathogens in the blood. Copyright © Houghton Mifflin Harcourt Publishing Company 9

What are some disorders of the lymphatic system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are some disorders of the lymphatic system? Lymphoma is a type of cancer that begins in the lymph nodes that can cause a swelling, or tumor. Lymphedema is a swelling of the body caused by blockage or injury to lymph vessels. Filariasis is a disease caused by threadlike worms called nematodes. Bubonic plague is a bacterial infection of the lymphatic system. Copyright © Houghton Mifflin Harcourt Publishing Company 10

Unit 1 Lesson 3 The Circulatory and Respiratory Systems The Heart of the Matter What are the parts of the cardiovascular system? The heart is a fist-sized organ that pumps blood around your body. The right side of the heart pumps oxygen-poor blood to the lungs. The left side of the heart pumps oxygen-rich blood to the body. Copyright © Houghton Mifflin Harcourt Publishing Company 11

What are the parts of the cardiovascular system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are the parts of the cardiovascular system? Each side of the heart has an upper and a lower chamber. Each upper chamber is called an atrium. Each lower chamber is called a ventricle. Blood enters the atria and pumps to the ventricles after passing through valves that keep blood from moving backward in the heart. Copyright © Houghton Mifflin Harcourt Publishing Company 12

What are the parts of the cardiovascular system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are the parts of the cardiovascular system? Blood is a type of connective tissue that contains cells, fluids, and other materials. Blood travels throughout the body in tubes called blood vessels. Three types of blood vessels are arteries, capillaries, and veins. Copyright © Houghton Mifflin Harcourt Publishing Company 13

What are the parts of the cardiovascular system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are the parts of the cardiovascular system? An artery carries blood away from the heart under high pressure. We call this pressure blood pressure. A capillary is a tiny blood vessel that allows exchanges between body cells and blood. A vein carries blood back to the heart. Valves in veins keep blood from flowing backward. Copyright © Houghton Mifflin Harcourt Publishing Company 14

It’s in the Blood What is blood made of? Unit 1 Lesson 3 The Circulatory and Respiratory Systems It’s in the Blood What is blood made of? The fluid part of blood is plasma, which is a mixture of water, minerals, nutrients, sugars, proteins, and waste. Platelets are tiny pieces of larger cells found in bone marrow. Platelets clump together to form blood clots when injury occurs. Copyright © Houghton Mifflin Harcourt Publishing Company 15

Unit 1 Lesson 3 The Circulatory and Respiratory Systems What is blood made of? White blood cells in the blood fight pathogens and keep you healthy. Antibodies are chemicals that identify pathogens. Red blood cells are disk-shaped cells that bring oxygen to every cell in the body. Red blood cells contain hemoglobin, which is an oxygen-carrying protein. Copyright © Houghton Mifflin Harcourt Publishing Company 16

How does blood move through the body? Unit 1 Lesson 3 The Circulatory and Respiratory Systems How does blood move through the body? Blood moves in two loops or circuits in the body. The flow of blood between the heart and the lungs is called pulmonary circulation. The circulation of blood between the heart and the rest of the body is called systemic circulation. Copyright © Houghton Mifflin Harcourt Publishing Company 17

How does blood move through the body? Unit 1 Lesson 3 The Circulatory and Respiratory Systems How does blood move through the body? Describe the movement of blood from the lungs, through the heart, to the body, and back again. Copyright © Houghton Mifflin Harcourt Publishing Company 18

How does circulation help maintain body temperature? Unit 1 Lesson 3 The Circulatory and Respiratory Systems How does circulation help maintain body temperature? Rising temperatures in the body cause blood vessels in the skin to widen, allowing heat to be transferred out of the body. Blood vessels get narrower to conserve heat when body temperature gets too low. Copyright © Houghton Mifflin Harcourt Publishing Company 19

What are some problems that affect the cardiovascular system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are some problems that affect the cardiovascular system? Atherosclerosis is a hardening of the artery walls caused by a buildup of cholesterol and other lipids. Hypertension is abnormally high blood pressure. Heart attacks and strokes are caused when arteries become blocked or burst. Copyright © Houghton Mifflin Harcourt Publishing Company 20

Take a Deep Breath What are the functions of the respiratory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems Take a Deep Breath What are the functions of the respiratory system? The respiratory system is the group of organs that take in oxygen and get rid of carbon dioxide. Respiration is the transport of oxygen from outside the body to cells and tissues and the transport of wastes out of the body. Copyright © Houghton Mifflin Harcourt Publishing Company 21

Breathe Easy What are the parts of the respiratory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems Breathe Easy What are the parts of the respiratory system? The mouth and nose take in air, which then flows to the pharynx, or throat. The pharynx braches into the esophagus, which leads to the stomach, and the larynx, which leads to the lungs. Copyright © Houghton Mifflin Harcourt Publishing Company 22

What are the parts of the respiratory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are the parts of the respiratory system? Air flows through the trachea, or windpipe, to the lungs. The trachea splits into two branches called bronchi, which connect to each lung. Each bronchus branches into bronchioles. Copyright © Houghton Mifflin Harcourt Publishing Company 23

What are the parts of the respiratory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are the parts of the respiratory system? The bronchioles lead to tiny sacs called alveoli, where gas exchanges take place. The diaphragm is a muscle below the ribcage and lungs that contracts as you inhale and relaxes as you exhale. Copyright © Houghton Mifflin Harcourt Publishing Company 24

What are the parts of the respiratory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are the parts of the respiratory system? Identify the main parts of the respiratory system. Copyright © Houghton Mifflin Harcourt Publishing Company 25

What are some disorders of the respiratory system? Unit 1 Lesson 3 The Circulatory and Respiratory Systems What are some disorders of the respiratory system? Asthma is a condition in which the airways are narrowed due to inflammation of the bronchi. Pneumonia is an inflammation of the lungs caused by bacteria or viruses. Emphysema occurs when alveoli have been damaged, resulting in poor oxygen transport. Copyright © Houghton Mifflin Harcourt Publishing Company 26