Science - Circulatory and Respiratory Systems

Lesson 2 **Types of circulatory system:** 1. **Open circulatory system** -- organisms with this type of system don't have a true heart or capillaries. 2. **Closed circulatory system** -- blood stays within blood vessels. In this way, blood is kept separate from body tissues. This system...

Lesson 2 **Types of circulatory system:** 1. **Open circulatory system** -- organisms with this type of system don't have a true heart or capillaries. 2. **Closed circulatory system** -- blood stays within blood vessels. In this way, blood is kept separate from body tissues. This system has a heart that pumps blood through a continuous circulation pattern. - "most hardworking" organ - Works as a pump to move the blood around the body - Has 4 chambers: 2 atria and 2 ventricles **Pericardium:** - Thin sac that surrounds your heart - Protects and lubricates your heart and keeps it in place within your chest **Parietal pericardium:** - Aids in the production of serous fluid secreted into the pericardial sac **Visceral pericardium:** - A.K.A epicardium - Innermost layer of your pericardium - Directly covers your heart & roots of your great vessels **4 chambers of the heart:** **Atria --** receives blood flowing back to the heart from various parts of the body. **Ventricles** -- pump blood out of the heart to various part of the body **How blood flows through the heart** 1. Right atrium takes in blood carrying carbon dioxide 2. Blood is squeezed down into the gith ventricle and taken to the lungs, where oxygen replaces carbon dioxide 3. Oxygen-carrying blood from the lungs enters the left atrium 4. Blood is pumped into the left ventricle and starts its journey again throughout the body **Blood -** Special fluid primarily contained within the blood vessels **Red blood cells**- carry oxygen, nutrients and water **White blood cells**- fights diseases and protects the body from infection **Platelets** -- gathers at the site of injury and help the clotting process **Plasma** -- straw colored liquid where the other components float in. Plasma is mostly water **Blood types** - determined by the presence or absence of certain antigens -- substances that can trigger an immune response if they are foreign to the body\\ **Blood vessels** -- tubes or channels that carry blood throughout our body **Aorta** -- largest blood vessel. Delivers nutrients and hormones **Superior vena cava** -- carries blood from [upper part] of the body to heart **Inferior vena cava** -- carries blood from [lower part] of the body to heart **Pulmonary** -- arteries carry blood from your heart to your lungs **Pulmonary veins** -- collect oxygen rich blood from your lungs and carry it to your heart **Sickle cell disease (SCD)** - inherited blood disorder. People with SCD have red blood cells that become hard and sticky, forming a C-shaped blood cell instead of the healthy disc-shaped Lesson 1 -lungs are the same size -Lungs are the only organ that can float in water **Respiratory system** -- group of organs that provide oxygen to the cells of the body **Oxygen** -- essential substance that cells need to produce energy **Carbon dioxide** -- by product of cellular respiration **Breathing mechanism** -- breathing is the physical process of the air getting in and out f lungs **Inspiration (inhalation)** -- movement of air from the external environment through the airways and into alveoli **Expiration (exhalation)** -- movement of air out of lungs **Cellular respiration** -- process by which chemical energy in food molecules is released and captured in the form of adenosine triphosphate (ATP) **Nose**: \- consist of the nostrils whose surfaces are lined with small hair that helps the nasal cavity screen harmful contaminents -serves as the primary entry part for air. **Nasal cavity:** \- filters incoming air/ removing dust and particles \- warms & humidifies are before entering -hollow space above and behind nose **Mouth/oral cavity** -- alternate entry point for air **Pharynx (throat):** -connects nasal cavity and mouth to trachea -serves as a common pathway for both air and food **Epiglottis:** \- flap like structure in pharynx \- prevents food from entering trachea **Nasopharynx:** \- Located at the back of the nasal cavity -contains nasopharyngeal tonsil **Oropharynx**: -Nasa likod ng mouth -Isthmus: connects nasal pharynx and oropharynx **Larynx (voice box)** -- tough, flexible segment. Tract connects pharynx, back of the mouth, throat to trachea windpipe **Trachea (windpipe):** \- wide hallow tube that connects the larynx to bronchi airways of the lungs \- helps achieve optimal humidity level **Bronchi:** \- Main airways to the lungs \- connects trachea to lungs **Cilia:** \- hair like structures \- helps mucus out your lungs **Bronchioles:** \- small branching air passages inside lungs **Alveoli:** -distributes oxygen to our blood -tiny air sacs located at the end of the bronchioles -where gas exchanges occur