Organ Systems and Cell Types in Biology

Organ Systems and Cells

• The human body is made of many specialized cells that work collectively.
• Each organ in the body is made of tissues, comprised of specialized cells.
• Organs work together in organ systems.
• Organ systems perform vital functions and work together to properly maintain the body's overall function.
• The levels of organization of the human body are: Cells > Tissues > Organs > Organ Systems > Organism. A similar hierarchy exists in the school system: Pupil > Form > Subject Class > Year > School.
• Frogs and humans have differing organ systems.
• All cells are living.
• Specialized cells come from pre-existing cells.

Cell Types and Stem Cells

• Human bodies contain over 200 different cell types.
• Stem cells are undifferentiated cells with the ability to divide and develop into specialized cells.
• Some stem cells can only become a few specialized cell types, while others have greater pluripotency.
• Examples of stem cells include those in the bone marrow, pancreas, and heart.
• Adult stem cells can repair damaged cells in various organs.
• Research suggests applications for stem cells in areas like disease treatment.

Animal Tissues

• Cells group together to form tissues.
• Four major types of tissues are: epithelial, connective, nerve, and muscle.

Epithelial Tissue

• Epithelial cells are closely packed and cover body surfaces and line internal organs.
• They can be single-layered for substance passage (e.g., oxygen) or multi-layered for protection (e.g., skin).

Connective Tissue

• Connective tissues support, protect, and connect organs.
• Composed of cells and non-living substances (e.g., blood, bone, ligaments).
• Blood carries oxygen and nutrients, removing waste.
• Bone is living tissue surrounded by hard non-living material.
• Ligaments connect bones.

Nerve Tissue

• Nerve tissue senses and responds to stimuli.
• Forms the brain, spinal cord, and nerves.
• Composed of sensory neurons (carrying information to the brain), motor neurons (carrying instructions from the brain), and interneurons (connecting sensory and motor neurons).

Muscle Tissue

• Muscle cells contract (shorten), enabling movement and organ function.
• Three types of muscle tissue: striated muscle (skeletal, voluntary), smooth muscle (involuntary, in organs like arteries), cardiac muscle (involuntary, in the heart).

Plant Tissues

• Plant tissues include xylem (water and mineral transport), phloem (food transport), periderm (protective tissue), and dermal tissue (outer layer).
• Vascular tissue includes xylem and phloem.

Organs and Organ Systems

• Organs are structures composed of multiple tissue types that perform specific tasks.
• Organ systems integrate various organs for specific bodily functions.
• The human body has 11 organ systems: Integumentary, Skeletal, Muscular, Lymphatic, Respiratory, Digestive, Nervous, Endocrine, Cardiovascular, Urinary, and Reproductive.

Respiratory System

• Includes the lungs, nasal passages, mouth, trachea, and bronchi.
• Function: taking in oxygen and releasing carbon dioxide.
• Cilia and mucus in the trachea/bronchi trap particles and propel mucus/debris upwards and out of the body.
• Breathing (inhalation/exhalation) is controlled by diaphragm and rib muscle movement.
• Breathing can become involuntary, but voluntary control is possible for specialized tasks.
• COPD (Chronic Obstructive Pulmonary Disease): encompasses several diseases, including asthma, emphysema, and chronic bronchitis, which obstruct airflow through the lungs. Common causes include smoking, second-hand smoke, and pollution.
• Other respiratory diseases: colds, influenza, SARS, and tuberculosis.

Circulatory System

• Composed of the heart, blood vessels, and blood.
• Blood is composed of red blood cells (carrying oxygen and carbon dioxide), white blood cells (fighting infection), platelets (blood clotting), and plasma (liquid component).
• The heart has four chambers and is controlled internally.
• Blood vessels: arteries (carry blood away from the heart), veins (carry blood to the heart), and capillaries (small vessels for gas/nutrient exchange).
• Blood circulates through the heart twice (through the right and left sides).
• Circulatory diseases: high blood pressure (increased blood pressure against vessel walls), coronary artery disease (blockage in coronary arteries), and stroke (interrupted blood flow to the brain).

Digestive System

• Functions to process food, absorb nutrients, and eliminate waste.
• Comprises the digestive tract (mouth, esophagus, stomach, small intestine, large intestine, anus) and accessory organs.
• Works closely with the circulatory system to transport absorbed nutrients throughout the body.
• Digestive diseases: food poisoning, irritable bowel syndrome (IBS), and colitis.

Cancer and Cell Division

• Cancer is uncontrolled cell division.
• A tumor is an abnormal mass of cells; a benign tumor is non-cancerous, while a malignant tumor is cancerous.
• Carcinogens are substances that cause cancer, such as smoke, certain chemicals, and radiation.
• Lifestyle choices to reduce cancer risk include maintaining a healthy weight, eating a balanced diet, exercising regularly, avoiding smoking, reducing alcohol intake, and getting regular checkups.

Cell Structure and Function

• Cell types and functions are highly specialized.

• Specialized cells come from other, pre-existing, specialized cells.

• Bone and muscles interact (work together) in various motions and systems via tissues and organ systems.

• Voluntary muscles are consciously controlled; involuntary muscles are controlled without conscious effort.

• The digestive tract components are mouth, esophagus, stomach, small intestine, and large intestine.

• Peristalsis is the movement of food through the digestive tract through muscle contractions.

• Plant Organelles

• Animal Organelles

• Cell Theory components

• Reasons for cell division

• Stages of the cell cycle (details for each stage)

• Steps in Mitosis (diagram and description of phases)

• Cancer definition

Explore the intricate structures of human organ systems and the various cell types that compose them. This quiz covers specialized cells, stem cells, and the hierarchy of biological organization, including comparisons with frog organ systems. Test your knowledge about how these components interact within the human body.