Lecture 1 Flashcards
Why do we study anatomy and physiology together?
Structure complements function. To fully understand how the body works, it’s important to understand both its structure (anatomy) and how it operates (physiology). The form of a structure often indicates its function; for example, bones support and protect organs because they are strong and hard.
Example: Bones support and protect organs because they are strong and hard.
What is the lowest level of structural organization in the body?
The atom is the smallest particle of an element that retains its properties. Atoms combine to form molecules, which form the foundation for all other levels of structure in the body.
Example: Hydrogen and oxygen atoms combine to form a water molecule (H₂O).
What is the next level of organization after atoms, and what are examples?
Molecules, which are combinations of atoms. Examples include water (H₂O), proteins, lipids, and carbohydrates, which all play critical roles in body function.
Example: Proteins are essential for building and repairing tissues in the body.
What is an organelle, and what are examples of cellular organelles?
An organelle is a specialized subunit within a cell that has a specific function. Examples include:
• Mitochondria: Generate energy (ATP) for the cell.
• Ribosomes: Synthesize proteins.
• Endoplasmic reticulum: Synthesizes and processes lipids and proteins.
• Golgi apparatus: Modifies and packages proteins for secretion or use within the cell.
Example: Mitochondria are known as the powerhouse of the cell due to their role in energy production.
What is a cell?
A cell is the fundamental structural and functional unit of a living organism. All living things are composed of cells, and cells can vary widely in size and shape depending on their function. For instance, nerve cells are long and thin to transmit signals, while red blood cells are small and disc-shaped to travel through blood vessels.
What is a tissue?
A tissue is a group of similar cells that work together to perform a specific function. The four basic tissue types are:
• Epithelial tissue: Covers body surfaces and lines body cavities.
• Connective tissue: Supports, protects, and binds other tissues.
• Muscle tissue: Produces movement.
• Nervous tissue: Transmits nerve impulses for communication and coordination.
What is an organ?
An organ is a structure composed of at least two (but usually all four) tissue types that perform a specific function for the body. For example, the stomach is an organ that digests food, and it contains muscle tissue for movement, epithelial tissue for lining, connective tissue for support, and nervous tissue for control.
What is an organ system?
An organ system is a group of organs that work closely together to achieve a common purpose. For example:
• The cardiovascular system: Composed of the heart and blood vessels, it transports blood, nutrients, oxygen, and wastes throughout the body.
• The digestive system: Includes organs like the stomach and intestines, working to break down food, absorb nutrients, and eliminate waste.
What is the anatomical position, and why is it important?
The anatomical position is a standard reference point used in anatomy to describe body parts and positions accurately. The body is erect, feet slightly apart, and palms face forward with thumbs pointing outward. This position ensures consistent and clear communication when describing anatomical structures.
What are the three most common body planes?
• Sagittal plane: Divides the body into right and left parts. A midsagittal plane is a specific sagittal plane that lies exactly in the midline, while a parasagittal plane is any sagittal plane offset from the midline.
• Frontal (coronal) plane: Divides the body into anterior (front) and posterior (back) parts.
• Transverse plane: Divides the body into superior (upper) and inferior (lower) parts. Also called a horizontal plane or cross-section.
What are the two major body cavities?
• Dorsal body cavity: Protects the nervous system. It has two subdivisions:
1. Cranial cavity: Encases the brain.
2. Vertebral (spinal) cavity: Encases the spinal cord.
• Ventral body cavity: Houses the internal organs (viscera). It has two subdivisions:
1. Thoracic cavity: Contains the heart (in the pericardial cavity) and lungs (in two pleural cavities).
2. Abdominopelvic cavity: Subdivided into the abdominal cavity (contains stomach, intestines, spleen, liver) and the pelvic cavity (contains bladder, reproductive organs, and rectum).
What separates the thoracic cavity from the abdominopelvic cavity?
The diaphragm, a dome-shaped muscle, separates the thoracic cavity from the abdominopelvic cavity and plays a major role in breathing.
What is homeostasis?
Homeostasis is the process by which the body maintains a stable internal environment despite external changes. It involves regulatory mechanisms that keep variables such as temperature, blood pressure, and pH within a narrow range to support optimal function and survival.
What separates the thoracic cavity from the abdominopelvic cavity?
The diaphragm, a dome-shaped muscle, separates the thoracic cavity from the abdominopelvic cavity and plays a major role in breathing.
Example sentence: The diaphragm contracts during inhalation to expand the thoracic cavity.
What is homeostasis?
Homeostasis is the ability of the body to maintain relatively stable internal conditions despite changes in the external environment. This dynamic state of equilibrium ensures that body functions like blood pressure, body temperature, and pH remain within a narrow, healthy range.
Additional information: Homeostasis is crucial for overall health and survival.
