Anatomy: Body Systems Overview

Anatomy

• Body Systems are groups of organs working together to perform specific functions
• Nervous system components include the brain, spinal cord, and nerves. Its function is to control bodily functions and respond to stimuli. Maintaining homeostasis involves regulating thoughts, emotions, and behavior.
• Cardiovascular system includes the heart, blood vessels, and blood. Its function is to transport oxygen, nutrients, and hormones throughout the body. Homeostasis is maintained by maintaining appropriate blood pressure and cardiac output.
• Respiratory system parts consist of the lungs, trachea, bronchi, and bronchioles. Its function is to exchange gases (oxygen and carbon dioxide) between the body and the environment. Homeostasis occurs via oxygen delivery to body cells and removal of carbon dioxide.
• Digestive system involves the mouth, esophagus, stomach, intestines, and associated organs. Its function is to digest food and absorb nutrients. Homeostasis relies on absorption of nutrients and water into the bloodstream.
• Urinary system includes kidneys, ureters, bladder, and urethra. Its function is to remove waste products from the blood and maintain fluid balance. Maintaining homeostasis depends on filtering blood and eliminating waste.

Homeostasis and Feedback

• Homeostasis is the process of maintaining a stable internal environment in the body.
• Negative Feedback is a regulatory mechanism to maintain homeostasis by countering deviations from an ideal set point.

Blood Sugar Homeostasis

• The diagram illustrates negative feedback loop to maintain blood sugar levels.
• Insulin, a hormone, reduces blood sugar by storing excess sugar in the liver.
• Glucagon, a hormone, increases blood sugar.
• Blood sugar is the variable being controlled.
• Hormones are the messenger molecules involved in this feedback system. Specifically, insulin and glucagon.

Nervous and Endocrine Systems

• Nervous system and endocrine system communicate by releasing hormones and nerve signals, respectively, to coordinate bodily functions.
• Hormones carry messages via the bloodstream, while nerves use electrical signals to relay messages quickly.

Enzymes in Digestion

• Enzymes are proteins that speed up chemical reactions in the digestive system. Different types of enzymes and locations.
• Location: In the digestive system, enzymes are present in various compartments, including the saliva, stomach, pancreas, and small intestine.
• Production: These digestive enzymes are manufactured in specialized cells within these glands/organs.
• Role: Different digestive enzymes are specific to different molecular components in food. They facilitate the breakdown of complex food molecules into simple absorbable nutrients.

Molecules of Life

• Six Common Elements: Six main elements make up most living things: carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur.
• Central Element: Carbon acts as the central element in most organic molecules.
• Organic vs. Inorganic: Organic compounds contain carbon, while inorganic ones do not. Organic are usually more complex molecules.
• Types of Bonds: Atoms can combine to form molecules through diverse chemical bonding mechanisms, including ionic, covalent, and hydrogen bonds.

Cells: Prokaryotic and Eukaryotic

• Prokaryotic and Eukaryotic cells are the two major categories based on their complexity and features. Eukaryotic cells are typically larger, more complex.
• Function of Organelles: Specific organelles perform crucial tasks within cells. Each has unique functions.

Cell Transport

• Cell Membrane: Structure of cell membrane, including phospholipids and proteins, creates a selectively permeable barrier.
• Active vs. Passive Transport: Active transport requires energy to move molecules against their concentration gradient, while passive transport does not.
• Diffusion: Movement of molecules from an area of high concentration to low concentration.
• Osmosis: Movement of water across a semipermeable membrane from an area of low solute concentration to high solute concentration.

Photosynthesis and Cellular Respiration

• Photosynthesis: Plants use light energy to convert carbon dioxide and water into glucose (sugar); the process involves two stages.
• Cellular Respiration: Organisms use oxygen to break down glucose, releasing energy in the form of ATP. This process also includes several stages.

DNA Structure, Replication and Mitosis

• DNA Replication: The process of creating two identical copies of a DNA molecule before cell division. It's a semi-conservative process using each old strand to make a new copy.
• Chromosomes: Chromosomes are organized structures containing DNA and proteins; Human cells have a specific number. There are also different types of chromosomes (autosomes and sex chromosomes).
• Mitosis: Cell Division.

Cell Cycle

• Interphase: The preparatory phase where the cell grows, replicates its DNA and prepares to divide.
• Mitosis: The process of nuclear division (prophase, metaphase, anaphase, telophase).
• Cytokinesis: Division of cytoplasm after nuclear division to produce two separate daughter cells.