Phisiology

• Cells are the basic structural and functional units of all living organisms.
• Homeostasis is the body's ability to maintain a stable internal environment despite external changes.
• The nervous system is a complex network of cells that transmit signals between different parts of the body.
• Tissues are groups of cells that work together to perform a specific function.
• The cardiovascular system is responsible for transporting oxygen, nutrients, hormones, and waste products throughout the body.
• The endocrine system is a collection of glands that produce and secrete hormones.
• The respiratory system is responsible for the exchange of oxygen and carbon dioxide in the body.
• The urinary system is responsible for the production, storage, and elimination of urine.
• The reproductive system is responsible for the production of offspring.
• The digestive system is responsible for breaking down food into nutrients that can be absorbed by the body.
• There are two main types of cells: prokaryotic cells, which lack a nucleus, and eukaryotic cells, which have a nucleus.
• The plasma membrane is a selectively permeable barrier that surrounds the cell and regulates the movement of substances in and out of the cell.
• The cytoplasm is the gel-like substance inside the cell that contains various organelles and is the site of many cellular processes.
• The nucleus is the control center of the cell and contains the genetic material, DNA.
• The endoplasmic reticulum (ER) is a network of membranes involved in the synthesis and transport of proteins and lipids.
• The heart is the main organ of the cardiovascular system and is responsible for pumping blood throughout the body.
• The heart is divided into four chambers: the left and right atria, and the left and right ventricles.
• The atria receive blood from the body and the lungs, while the ventricles pump blood out to the body and the lungs.
• The heart is regulated by electrical signals that control the timing and coordination of its contractions.
• The blood vessels in the cardiovascular system include arteries, veins, and capillaries.
• There are four main types of tissues in the human body: epithelial, connective, muscle, and nervous.
• Epithelial tissue covers the surfaces of the body, lines organs and cavities, and forms glands.
• Connective tissue provides support and connects different structures in the body.
• Muscle tissue is responsible for movement and can be categorized into three types: skeletal, cardiac, and smooth.
• Nervous tissue is specialized for communication and coordination in the body.
• It is divided into two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS).
• The CNS consists of the brain and spinal cord, while the PNS includes all the nerves outside of the CNS.
• The nervous system is responsible for controlling and coordinating all bodily functions.
• Neurons are the basic building blocks of the nervous system and are specialized cells that transmit electrical signals.
• There are three types of neurons: sensory neurons, motor neurons, and interneurons.
• The hypothalamus plays a key role in regulating homeostasis by receiving and interpreting signals from the body and initiating appropriate responses.
• One of the main mechanisms of homeostasis is negative feedback, where the body's response opposes the initial change to bring the system back to its set point.
• Examples of homeostasis in the body include maintaining body temperature, blood glucose levels, pH balance, and blood pressure.
• When body temperature rises, blood vessels dilate and sweat is produced to cool the body down and maintain a stable temperature.
• If blood glucose levels drop, the pancreas releases glucagon to stimulate the liver to release stored glucose, raising blood sugar levels back to normal.
• Hormones are chemical messengers that regulate various bodily functions.
• The major glands of the endocrine system include the pituitary gland, thyroid gland, adrenal glands, pancreas, and ovaries/testes.
• The pituitary gland, often referred to as the "master gland," controls the release of hormones from other glands.
• The thyroid gland produces hormones that regulate metabolism, growth, and development.
• The adrenal glands produce hormones that help the body respond to stress and regulate blood pressure.