Module 2 - Cellular Physiology Flashcards
What are the principles of cell theory?
- Cells are the smallest structural and functional unit capable of life
- Functionality depends on anatomy of specific cells
- Cells are living building blocks of all organisms
- An organism’s anatomy and physiology depend on the individual and collective characteristics of its cell’s anatomy and physiology
- All new cells and new life arise only from pre-existing cells
- Cells of all organisms fundamentally similar in anatomy and physiology
How many specialized cell types exist in the human body?
About 200
What are 3 major parts of all cells, regardless of specialization?
o Plasma membrane
o Nucleus
o Cytoplasm
What is the structure and function of the plasma membrane?
- Lipid occurs in 2 layers, called a bilayer with a sandwich-like structure
- Composed primarily of proteins and lipids, especially phospholipids
- Substantial amounts of cholesterol (also a lipid) that helps stabilize the membrane
- Acts as a selective barrier between cellular contents and extracellular fluid
- Controls traffic in and out of the cell
What is the structure and function of the nucleus?
- Contained in every human cell except red blood cells
- Composed primarily of histone protein and DNA enclosed in a double-layered membrane
- Acts as a control center of the cell, providing storage of genetic information
- Nuclear DNA provides codes for synthesis of structural and enzymatic proteins and serves as blueprint for cell replication
What is the structure and function of the endoplasmic reticulum?
• Extensive, continuous membranous network of fluid-filled tubules and flattened sacs
• Forms new cell membrane and other cell components and manufactures products for secretion
May be smooth or rough
What is rough endoplasmic reticulum?
- Endoplasmic reticulum studded with ribosomes
* The ribosomes are where the amino acids are chemically linked to form proteins
What is smooth endoplasmic reticulum?
- No ribosomes present
- Site of lipid and membrane synthesis
- Site of calcium storage
What is the structure and function of the Golgi complex?
- Series of flattened sacs usually curled at the edges
- Proteins and lipids are modified, packaged, and distributed from here
- The sacs pinch off bits of themselves to form vesicles that contain the products as they move to their final destination
What is the structure and function of the lysosomes?
- Derived from sacs of the Golgi body
- Contains hydrolytic enzymes break down particles of food taken into the cell and make the products available to the cell
- Destroy foreign substances and cellular debris
What is the structure and function of the centriole?
• Usually paired, small barrel-shaped organelles that consist of nine short triplet microtubules
• Site of growth of new microtubules including
o Cytoplasmic transport microtubules
o Microtubules that form the mitotic spindle
What is the structure and function of the peroxisomes?
- Membranous sacs containing oxidative enzymes
* Perform detoxification activities
What is the structure and function of the mitochondria?
• Often called powerhouses of the cell
• Rod or oval shaped bodies enclosed by 2 membranes
o Inner membrane folded into cristae that project into an interior matrix
• Carbohydrates, lipids, and proteins broken down here to form ATP (adenosine triphosphate)
• Contains enzymes for citric acid cycle and electron transport chain
• The site where oxygen you breathe used in “cellular respiration”
What is the structure and function of the vaults?
- Shaped like hollow octagonal barrels
* Serve as cellular trucks for transport from nucleus to cytoplasm
What is the structure and function of the intermediary metabolism enzymes?
- Dispersed within the cytosol
* Facilitate intracellular reactions involving the degradation, synthesis, and transformation of small organic molecules
What is the structure and function of the ribosomes?
- Granules of RNA and proteins
- Some attached to rough endoplasmic reticulum, some free in the cytoplasm
- Serve as workbenches for protein synthesis
What is the structure and function of the transport, secretory, and endocytotic vesicles?
- Transiently formed, membrane-enclosed products synthesized within or engulfed by the cell
- Transport and/or store products being moved within, out of, or into the cell, respectively
What is the structure and function of the inclusions within the cytosol?
- Glycogen granules, fat droplets
* Store excess nutrients
What is the structure and function of the microtubules?
• Long, slender, hollow tubes composed of secretory vesicles
• Maintain asymmetric cell shapes and tubulin molecules
• Coordinate complex cell movements, specifically
o Facilitating transport of secretory vesicles within cells
o Serving as main structural and functional component of cilia and flagella
o Forming mitotic spindle during cell division
What is the structure and function of the microfilaments?
• Intertwined helical chains of actin molecules
• Composed of myosin molecules (also present in muscle cells)
• Play a vital role in various cellular contractile systems including
o Muscle contraction
o Ameboid movement
• Serve as mechanical stiffener for microvilli
What is the structure and function of the intermediate filaments?
- Irregular, threadlike proteins
* Help resist mechanical stress
What is intermediary metabolism and where does it occur?
- Chemical reactions inside the cell that involve degradation, synthesis, and transformation of small organic molecules
- Captures energy and provides raw materials for cell functions
- All occur in cytosol
What are anabolic reactions and what does it require?
- Synthesis of molecules that build up organs
* Requires building blocks and energy to be present
What are catabolic reactions?
• Breakdown complex molecules into simpler ones