Lesson 1.1 ( Organisation of the Body ) Hierarchy of organization in our body: 1. 2. 3. 4. Cells: smallest living unit of the human body Tissues: similar cells grouped together Organs: structures composed of several tissues. Body systems: a group of organs working together for specific functions. The body's systems work together to maintain proper function of the body. Circulatory System Function: Transports substances like oxygen (O2), water (H2O), nutrients to the body cells and remove waste such as carbon dioxide (CO2) from the body Parts: 1. 2. 3. ● ● Heart, blood vessels (()وعاء دموي: arteries ()الشرايين, veins ()عروق, and capillaries ()الشعيرات الدموية, blood Red ( arteries ) carry oxygenated blood Blue ( veins ) carry deoxygenated blood Respiratory System Function: ● Moves air into and out of lungs; controls gas exchange between blood and lungs Parts: ● ● ● ● ● Nose mouth trachea bronchi lungs Digestive System Function: ● Digests food and absorbs nutrients from food; removes waste Parts: ● ● ● ● ● ● ● ● ● ● mouth salivary glands, pharynx, esophagus, stomach, small and large intestine, rectum, pancreas, liver, gall bladder Renal/ Urinary System Function: ● removes wastes from blood; regulates the concentration of body fluids Parts: ● ● ● ● kidneys ureters urinary bladder urethra Musculoskeletal system Bones Function: ● Skeleton supports and protects organs ● ● ● Gives the body shape Allows movement Bone marrow makes new blood cells ● Store minerals Muscles Function: ● ● Muscles allow for movement Some muscles are voluntary and some are involuntary ○ Example- Biceps muscle ○ Heart is involuntary ○ smooth muscles are also involuntary. ( found in the stomach ) Endocrine System Function: Produce hormones that regulate many functions such as growth, development, and metabolism. Examples of endocrine glands and their hormones Pancreas- Insulin Thyroid gland- Thyroxine ( regulates body temperature) Pituitary gland- Growth hormone ● ● the function of hormones is not where they are made ( the function around the entire body ) gland is an organ that produces hormones ( they are all parts of the endocrine system ) Nervous System Function: ● Regulates behavior; maintains homeostasis; regulates other organ systems; controls sensory and motor functions Parts: ● ● ● Brain spinal cord nerves. Homeostasis: is the maintenance of a constant internal environment. ● ● Examples of homeostasis are regulating body temperature, blood glucose levels and water content. The nervous system and endocrine system are involved in homeostasis. Lesson 1.2 ( Circulatory and Respiratory Systems ) Parts: ● The circulatory system is made of the ○ I. heart ○ II. the blood ○ III. the blood vessels ()وعاء دموي Function: ● The role of the circulatory system is to allow blood to circulate around the body and transport nutrients to and from the cells. The Heart: ● ● ● The heart is a muscular organ, which pumps blood through the blood vessels. Blood transports oxygen and nutrients (such as glucose). Blood also helps remove waste substances such as carbon dioxide. The Blood: ● ● Blood is a body fluid that is constantly circulating The average person has about 5 liters of blood circulating in the body Blood is made of: ● ● ● ● Plasma liquid part of blood Red blood cells containing hemoglobin White blood cells Platelets Plasma: ● ● Plasma is the liquid portion of blood. About 55% of our blood is plasma; which is mostly water. The main role of plasma is to take nutrients, oxygen, hormones, and proteins to the parts of the body that need it. ● Cells also put their waste products into the plasma. The plasma then helps remove this waste from the body. Red Blood Cells: RBC’s= Most common type of blood cells in the blood that contain hemoglobin. ● Hemoglobin carries oxygen to the body's tissues White Blood Cells: WBCs = part of the body's immune system. ● They help the body fight infection and other diseases Platelets: Platelets are small, colorless cell fragments in our blood. ● Their job is to form clots and stop or prevent bleeding. Bone Marrow ● ● Bone marrow contains stem cells that develop into red blood cells, white blood cells, and platelets. stem cells: They are cells from which all other cells with specialized functions are come from. They mostly live in the bone marrow. The Blood Vessels ● ● ● ● ● Blood moves through the blood vessels There are 3 types of blood vessels: Arteries, Veins, Capillaries Systemic circuit: from heart to body Pulmonary circuit: from heart to lungs Diseases of the cardiovascular: ● ● ● ● Hypertension-high blood pressure= ضغط دم مرتفع Heart attack- نوبة قلبية Angina-chest pain Stroke- السكتة الدماغية Respiratory System Parts of the respiratory system: it allows: 1. air to pass in and out of the body. 2. gas exchange happens 1. it happens in the alveoli 2. the gases exchanged are carbon dioxide ( CO2) and oxygen (O2) Gas Exchange: ● happens in the alveoli ○ Oxygen moves from the alveoli into the blood and carbon dioxide moves from the blood into the alveoli. ○ Features of alveoli ( air sacs ): ■ then walls ( one cell thin ) ■ large surface area ■ moist surface ■ many blood capillaries Diffusion ( gas exchange ) ● is the movement of gases/molecules from an area of high concentration to an area of low concentration. How does gas exchange take place at the alveoli? ● ● Carbon dioxide is in high concentration in the capillary (deoxygenated blood) and low concentration in the alveoli. Carbon dioxide diffuses from the capillary into the alveoli: this means it leaves the blood and enters the lungs to be exhaled out. Oxygen is in low concentration in the capillary but in high concentration in the alveoli. When a person inhales oxygen, it diffuses from the alveoli into the capillary. Blood is now oxygenated. Diseases of the respiratory system: ● Chronic Obstructive Pulmonary Disease COPD ○ A group of diseases of the lungs that lead to chronic inflammation and obstruction of the airways. ○ Symptoms include breathing difficulty, cough, mucus ( )المخاطproduction and wheezing. ○ It's typically caused by long-term exposure to irritating gases, most often from cigarette smoke ○ People with COPD are at high risk of developing heart disease, lung cancer and a variety of other conditions. ● Pneumonia ○ Pneumonia is an infection ( )**عدوىthat inflames the air sacs (alveoli)**. ○ Symptoms include cough, fever, chills, and trouble breathing. ● Asthma ○ Asthma is a chronic lung disease affecting people of all ages. ○ It is caused by inflammation and muscle tightening around the airways, which makes it harder to breathe. ○ Symptoms can include coughing, wheezing, shortness of breath and chest tightness. These symptoms can be mild or severe and can come and go over time. Lesson 1.3 (Digestive System ) Digestion: the process of breaking down food we eat into nutrients that our body can absorb and use. ● digestion begins in the mouth 3 functions of the digestive system: ● ● ● digestion absorption excretion Nutrients: ● ● ● ● ● ● Carbohydrates Protein Fats Vitamins Minerals Water Process and outcomes of digestion: Pathway: ● ● it is 9 meters long 6 meters is the small intestine Mouth ● ● ● digestion starts in the mouth saliva is secreted in the mouth two types of digestion happen in the mouth: ○ Mechanical digestion: breaking food into smaller pieces by chewing ○ Chemical digestion: breaking food down using enzymes ■ Enzymes: proteins that speed up chemical reactions ■ Saliva contains enzymes that break down carbohydrates Esophagus: ● ● ● The esophagus is a strong muscular tube that leads to the stomach. The esophagus receives the food when you swallow. Using peristalsis, the esophagus delivers food to your stomach. ○ Peristalsis: refers to contractions of smooth muscles ( make up the esophagus ) that move food down the digestive system. Stomach ● the hollow organ ( container ) that holds food while it is being broken down further. ● Cells in the lining of the stomach secrete a strong acid (Hydrochloric acid - HCl) and enzymes. These continue to break down food, especially protein. Small Intestine ● ● ● The small intestine has 3 parts - Duodenum, ( closer to the stomach) Jejunum, Ileum ( closer to the large intestine). 6-meter-long muscular tube – about 31/2 times the length of your body! In the small intestine, digestion is completed and nutrients are absorbed into the bloodstream Pancreas and Liver ● ● ● ● ● Food is broken down in the small intestine with the help of the pancreas and liver. The pancreas secretes digestive enzymes into the duodenum. These enzymes completely break down protein, fats, and carbohydrates ○ The liver also helps to detoxify (remove toxic substances) from food. ○ Proteins are broken down into amino acids ○ Carbohydrates are broken down into simple sugars (glucose) ○ Fats are broken down into fatty acids and glycerol Bile ( not an enzyme ) from the liver helps to digest fat. Bile is a green-brown liquid produced by the liver and stored in the gallbladder. The liver also has the job of removing toxic and harmful chemicals from food. The tubes connecting the three organs are called a duct Absorption of Nutrients: ● ● ● Most absorption happens in the small intestine. Nutrients - Carbohydrates, protein, fat, minerals, and vitamins are mainly absorbed here. These nutrients are absorbed by the finger-like projections villi, (which cover the inner walls of the small intestine) directly into the blood through a process called diffusion. Villi include: ● ● ● arteries ( carb protein ) veins lymphatic vessel ( part of the lymphatic system ). ( fat ) ○ yellow. because it contains lymph (yellow-colored substance ) Diffusion ● ● movement of molecules from high to low concentration In the digestive system: ○ In the small intestine, the nutrients move from the digestive tract (area of high concentration of nutrients) to the blood (area of low concentration of nutrients). Large Intestine ( ) قولون ● ● ● ● ● ● ● ● The large intestine is responsible for processing waste. By the process of peristalsis, the food that is not digested, moves through the colon. The stool is leftover waste from the digestive process. As stool passes through the colon, water is reabsorbed and removed from the stool. It takes about 36 hours (1.5 days) for stool to get through the colon. The liquid that enters the large intestine is mostly food debris (food waste), fiber and bad bacteria, which are not absorbed in the small intestine. Fiber ( comes from a plant food ) (the layer around this plant food) cannot be digested by the digestive system. We also have ‘good’ bacteria which live in our digestive system, and they have several important functions, such as: ○ producing some vitamins (such as Vitamin K and Biotin) ○ breaking down waste products and food particles ○ protecting against harmful bacteria. Rectum ( end of large intestine ) ● ● At the end of the large intestine is the rectum. It holds stool until it can be passed out of the body. When the rectum becomes full, it gives off a signal to the brain that it's time to go to the bathroom.
