Muscular, Reproductive, and Digestive Systems: Functions and Organs
Muscular System: Functions and Purpose
Each muscle type in the muscular system has a specific purpose. You are able to walk because of your skeletal muscles. You can digest because of your smooth muscles. And your heart beats because of your cardiac muscle.
The different muscle types also work together to make these functions possible. For instance, when you run (skeletal muscles), your heart pumps harder (cardiac muscle), and causes you to breathe heavier (smooth muscles).
Reproductive System: Male and Female Organs
Humans are sexual, meaning that both a male and a female are needed to reproduce. Each is equipped with specific organs capable of producing specific cells needed to procreate.
In conjunction with a woman’s reproductive organs, sexual intercourse can lead to the reproduction of human life.
Male Reproductive Organs
For men, the external reproductive organs include:
- Penis: This tubular, muscular organ fills with blood during arousal, thus making sexual intercourse possible.
- Scrotum: This pouch-like sac hangs below the penis and encases the testes, or testicles.
- Testicles: These two oval-shaped organs produce sperm cells and testosterone.
Female Reproductive Organs
The major organs of the female reproductive system include:
- Vagina: This muscular tube receives the penis during intercourse and through it a baby leaves the uterus during childbirth.
- Uterus: This organ holds and nourishes a developing fetus if an egg was properly fertilized.
- Ovaries: The female gonads, the ovaries produce ova. When one matures, it is released down into a fallopian tube.
- Fallopian tubes: These small tubes transport ova from the ovaries to the uterus. This is where an egg waits to be fertilized.
Digestive System: How Your Body Processes Food
The human digestive system is the means by which tissues and organs receive nutrients to function. The system breaks down food, extracts nutrients from it, and converts them into energy.
The digestive tract begins this involuntary process once food is consumed. Saliva begins the breakdown of food, and other enzymes in the digestive tract extend this process. As digestion continues, the food is propelled from organ to organ through muscular contractions called peristalsis.
Major Organs of the Digestive System
The largest parts of the digestive system include:
- Esophagus: A hollow tubular organ in the neck and chest area that connects the mouth to the stomach. Muscles here propel food to the stomach.
- Stomach: A large organ that holds and digests food through a cocktail of enzymes and acids. Food remains here for two to eight hours.
- Liver: This organ helps filter toxins from the blood and produces bile, which helps break down proteins, carbohydrates, and fats.
- Gallbladder: This sac-like organ stores bile produced by the liver and then releases it as necessary.
- Pancreas: This organ produces insulin, which aids in the metabolism of sugars.
- Small intestine: The small intestine receives food from the stomach and begins to break down the food while absorbing the majority of its nutrients.
- Large intestine: This organ is filled with billions of harmless bacteria that turn food into feces while removing water and electrolytes for the body’s use.
- Rectum: At the end of the large intestine, this small space is a temporary storage area for feces.
- Anus: This is the external opening of the rectum, through which feces are expelled.