Digestive System Quiz

Organ Systems

• The human body is made up of six major organ systems.
• Cells make up tissues, tissues make up organs, and organs make up organ systems.
• The organ systems are responsible for various functions crucial for survival.

Digestive System

• Involved in breaking down and absorbing food.
• Digestion begins in the mouth with physical breakdown by teeth and chemical breakdown by saliva enzymes.
• Key components: teeth, saliva, enzymes.
• Different sources of energy for organisms include carbohydrates (sugars/starches), lipids (fats/oils), and proteins.
• Cellular use of energy requires these sources to be broken down.
• The digestive system accomplishes this breakdown.
• Digestion includes physical/mechanical breakdown and chemical breakdown using enzymes.
• Enzymes are proteins that break down substances into smaller pieces.
• The building blocks of carbohydrates are glucose.
• The building blocks of fats are lipids.
• The building blocks of proteins are amino acids.

Digestive System - Components

• Salivary amylase begins chemical digestion by breaking down starch molecules into smaller sugar molecules.
• Saliva contains amylase.
• Food is broken down into smaller pieces by the teeth, then it moves to the stomach where it is churned and mixed with gastric juice.
• Gastric juice is made of mucus, hydrochloric acid, and enzymes that allow for the chemical breakdown of food into smaller particles.
• The esophagus is a tube-like organ that carries food from the throat to the stomach.
• The stomach mechanically breaks down more food, mixes it with gastric juice, and pushes it into the small intestine.
• The small intestine breaks down starches/carbohydrates, proteins, and lipids into smaller pieces with the help of enzymes.
• The liver produces bile that breaks down fat.
• The gallbladder stores bile and releases it into the small intestine.
• Enzymes secreted from the pancreas help break lipids, carbohydrates, and proteins down.
• The small intestine absorbs the nutrients.
• The large intestine absorbs water, vitamins, and minerals.
• Any undigested food is formed into feces and collected in the rectum.
• The average male's digestive track is 9 meters long.
• The digestive system is a long tube.
• The digestive system starts at the mouth and ends at the rectum.

Other Key Points

• The human gut contains 100 trillion bacteria, outnumbering your own cells 10:1.
• Healthy gut bacteria help digest food and extract vitamins.
• Bacteria outnumber your own cells' 10 to one and make up about 1-3% of your body mass.
• The respiratory system is responsible for supplying the blood with oxygen and removing carbon dioxide.
• The respiratory system uses the actions of the rib cage and diaphragm (muscle) to move air in and out of the lungs.
• Capillaries surround the alveoli.
• Lungs: remove carbon dioxide.
• Heart: pumps oxygenated blood throughout the body and receives deoxygenated blood from the body.
• Kidneys: filter waste products like urea, water, and salts.
• The blood is filtered about 300 times in one day in an average person.
• In average, about 1.5L of urine is released per day.

Circulatory System

• Transports nutrients, oxygen, and removes waste products.
• The circulatory system has three main responsibilities: delivering absorbed nutrients to each cell, delivering oxygen to each cell, and removing waste products from each cell.
• The length of all the blood vessels, together, is about 2 ½ times around the Earth.
• The system includes the heart, blood vessels (arteries, veins, capillaries), and blood (red blood cells, white blood cells, platelets, plasma).
• Heart has four chambers: right atrium, left atrium, right ventricle, left ventricle.
• Heart pumps blood to the lungs and body and receives blood from them.

Muscular System

• Muscles help you move.
• You have different types of muscles - skeletal, smooth, and cardiac.
• Muscles are important for movement.

Skeletal System

• Forms the framework of the body.
• Provides structure and support.
• Protection for internal organs.
• The Skeleton is attached to Muscles in the body that help you move.

Nervous System

• Communicates information throughout the body.
• Two main components: central nervous system (CNS) and peripheral nervous system (PNS).
• The CNS includes the brain and spinal cord.
• The PNS includes nerves that extend to all parts of the body.
• Neurons (cells) form the nervous system; send and receive messages.
• Three main parts of the brain are, Cerebrum, Cerebellum, Medullla.

Other Information

• Blood is composed of different components—red blood cells (carry oxygen), white blood cells (fight infection), platelets (help with clotting), and plasma (liquid part of the blood).
• The smallest functional unit of a kidney is called a nephron.
• The role of a nephron is to filter waste from the blood and produce urine.
• Blood is filtered through the kidneys about 300 times each day.
• A few diseases of the lungs and kidneys are COPD (damage to the lungs), lung cancer, and cystic fibrosis.