Mitosis and Meiosis. Animations. How cells divide. How do we smell? - Rose Eveleth. All you ever wanted to know about Germs. What would happen to your body without water? Muscular System: Facts, Functions & Diseases. While most people associate muscles with strength, they do more than assist in lifting heavy objects.
Nervous System: Facts, Function & Diseases. The nervous system is a complex collection of nerves and specialized cells known as neurons that transmit signals between different parts of the body.
Vertebrates — animals with backbones and spinal columns — have central and peripheral nervous systems. The Human Body: Anatomy, Facts & Functions. Human body systems.Credit: Image via Shutterstock The human body is everything that makes up, well, you.
The basic parts of the human body are the head, neck, torso, arms and legs. Body systems Our bodies consist of a number of biological systems that carry out specific functions necessary for everyday living. Skin: Facts, Diseases & Conditions. While it may not immediately come to mind when asked to name the body’s major organs, the integumentary system, or skin, is its largest organ.
It comprises the skin as well as hair and nails, which are appendages of the skin. In humans, this system accounts for about 15 percent of total body weight. Urinary System: Facts, Functions & Diseases. The urinary system – also known as the renal system – produces, stores and eliminates urine, the fluid waste excreted by the kidneys.
The urinary system includes two kidneys, two ureters, the bladder, two sphincter muscles and the urethra. Description of the urinary system The urinary system works with the lungs, skin and intestines to maintain the balance of chemicals and water in the body. Adults eliminate about a quart and a half (1.42 liters) of urine each day, depending on the amount of fluid consumed and fluid lost through perspiring and breathing. Certain types of medications, such as diuretics that are sometimes used to treat high blood pressure, can also affect the amount of urine a person produces and eliminates. Respiratory System: Facts, Function and Diseases. The human respiratory system is a series of organs responsible for taking in oxygen and expelling carbon dioxide.
The primary organs of the respiratory system are lungs, which carry out this exchange of gases as we breathe. Red blood cells collect the oxygen from the lungs and carry it to the parts of the body where it is needed, according to the American Lung Association. During the process, the red blood cells collect the carbon dioxide and transport it back to the lungs, where it leaves the body when we exhale. The human body needs oxygen to sustain itself. A decrease in oxygen is known as hypoxia and a complete lack of oxygen is known as anoxia and, according to MedLine Plus. Skeletal System: Facts, Function & Diseases. The adult human skeletal system consists of 206 bones, as well as a network of tendons, ligaments and cartilage that connects them.
The skeletal system performs vital functions — support, movement, protection, blood cell production, calcium storage and endocrine regulation — that enable us to move through our daily lives. Animals with internal skeletons made of bone, called vertebrates, are actually the minority, as 98 percent of all animals are invertebrates, meaning they do not have internal skeletons or backbones. Human infants are born with 300 to 350 bones, some of which fuse together as the body develops. By the time most children reach the age of 9 they have 206 bones. The skeletons of adult males and females have some variation, primarily to accommodate childbirth. Reproductive System: Facts, Functions and Diseases. Lymphatic System: Facts, Functions & Diseases. The primary function of the lymphatic system is to transport lymph, a clear, colorless fluid containing white blood cells that helps rid the body of toxins, waste and other unwanted materials.
Lymphatic comes from the Latin word lymphaticus, meaning "connected to water," as lymph is clear. Immune System: Diseases, Disorders & Function. Endocrine System: Facts, Functions and Diseases. The endocrine system is the collection of glands, each of which secretes different types of hormones that regulate metabolism, growth and development, tissue function, sexual function, reproduction, sleep and mood, among other things.
The word endocrine derives from the Greek words "endo," meaning within, and "crinis," meaning secrete. Digestive System: Facts, Function & Diseases. The human digestive system is a series of organs that converts food into essential nutrients that are absorbed into the body and moves the unused waste material out of the body.
It is essential to good health because if the digestive system shuts down, the body cannot be nourished or rid itself of waste. Description of the digestive system The digestive tract, also known as the gastrointestinal (GI) tract, starts at the mouth, continues to the esophagus, stomach, small intestine, large intestine (commonly referred to as the colon) and rectum, and ends at the anus. The entire system — from mouth to anus — is about 30 feet (9 meters) long. Digestion begins with chewing. Swallowing pushes chewed food into the esophagus, where it passes through the oropharynx and hypopharynx. The stomach’s gastric juice, which is primarily a mix of hydrochloric acid and pepsin, starts breaking down proteins and killing potentially harmful bacteria.
Whatever material is left goes into the large intestine. CellCraft. Six myths about vaccination – and why they’re wrong. A pear has 600 times more formaldehyde in it than a vaccine does, writes Rachael Dunlop. Image: Oksana Kuzmina/Shutterstock Recently released government figures show levels of childhood vaccination have fallen to dangerously low levels in some areas of Australia, resulting in some corners of the media claiming re-ignition of “the vaccine debate”. You can check how your postcode rates here. Well, scientifically, there’s no debate.
In combination with clean water and sanitation, vaccines are one of the most effective public health measures ever introduced, saving millions of lives every year. Melting Glaciers Liberate Ancient Microbes. Editor's Note: This article is an extended version of "Bugs in the Ice Sheet" from the May 2012 Issue of Scientific American. BOZEMAN, Mont. —Locked in frozen vaults on Antarctica and Greenland, a lost world of ancient creatures awaits another chance at life. Like a time-capsule from the distant past, the polar ice sheets offer a glimpse of tiny organisms that may have been trapped there longer than modern humans have walked the planet, biding their time until conditions change and set them free again.
With that ice melting at an alarming rate, those conditions could soon be at hand. Masses of bacteria and other microbes – some of which the world hasn't seen since the Middle Pleistocene, a previous period of major climate change about 750,000 years ago – will make their way back into the environment. Once thought to be too harsh and inhospitable to support any living thing, the ice sheets are now known to be a gigantic reservoir of microbial life. Could this be Jurassic Park on Ice? GMO - What Is It? After Life: The Science Of Decay (BBC Documentary) Interactive Tutorials and Quizzes On Human Anatomy and Physiology. Human Anatomy Model, Anatomy Chart, Anatomical Chart. Interactive 3D Human Anatomy. Home of CELLS alive!