Biomed Cells

Histology/micro anatomy

The study of the structure and function of cells and tissues on a microscopic scale

Cell

The basic, living, structural, and functional unit of the body

Cytology

The study of cell structure

Cell physiology

The study of cell function

Cytology and cell physiology

What are the two branches of cell study?

Tissue

Group of cells with a common function

Organs

Independent body part formed from tissue

System

Organs functioning together

Nucleus, cytoplasm, plasma membrane

What are the three main parts of the cell?

Cytosol, cytoskeleton, organelles

What are the three things within the cytoplasm?

Cytosol

What is the fluid portion of the cytoplasm?

Cytoskeleton

What is the network of protein, tubules and filaments in the cytoplasm?

Organelles

What things in the cytoplasm possess a unique structure and perform specific functions

Plasma membrane

The structure of the cell with the flexible sturdy barrier that separates the inside in the outside of the cell?

Plasma membrane

What structure of the cell is the fluid mosaic model? (The membrane that resembles a continuously moving sea of fluid lipids containing a mosaic of proteins.)

Lipid bilayer

What type of layer does the plasma membrane have?

Integral and peripheral membrane proteins

What are the two types of proteins in the lipid bilayer of the plasma membrane?

Phospholipids (75%), cholesterol (20%), and glycolipids (5%)

What three lipid molecules make up the lipid bilayer

The hydrophilic polar head (faces outward) and the hydrophobic nonpolar tails (faces inward)

What makes lipid molecules amphipatic?

The hydrophobic nonpolar tails

Which lipid molecule forms, the hydrophobic core of the bilayer

Integral membrane proteins

Membrane proteins that extend halfway into or across the entire lipid bilayer and are firmly embedded in the plasma membrane

Peripheral membrane proteins

Membrane proteins, located on the inner or outer surface of the plasma membrane and are not embedded in the plasma membrane

Selective permeability

What type of permeability does the plasma membrane exhibit?

Small nonpolar, uncharged molecules (oxygen, carbon dioxide)

What is the lipid bilayer permeable to?

Uncharged polar molecules (water)

What is the lipid bilayer slightly permeable to?

Ions and charged or large uncharged polar molecules (glucose)

What is the lipid by layer in permeable to?

Ion channels

Integral membrane proteins that form tiny pores across the plasma membrane that allows specific ions to enter or exit the cell

The potassium ion channel

What is an example of an ion channel?

Transporters/carriers

Integral membrane proteins that assist transport of specific molecules across the plasma membrane

The glucose transporter

What is an example of a transporter?

Exocytosis

The transport of materials in a vesicle formed within a cell going to the extra cellular environment; starting inside and going outside

Endocytosis

The uptake of materials from the extracellular environment, going into a vesicle formed from the plasma membrane; starting outside and going inside

Vesicle

A membranous sac containing the materials to be transported in the lumen or in the membrane; has a lipid bilayer

Phagocytosis

The specific type of endocytosis; the ingestion of a solid particle from the extracellular environment in a vesicle

Lysosomal enzymes

In phagocytosis, what will the engulfed materials be broken down by?

Phagocytes

In phagocytosis the engulfed materials that were broken down are carried out by what

Macrophages (in tissue) and neutrophils (in blood)

What are the two phagocytes?

Pseudopods

During phagocytosis, what extends to form a phagosome

Cytoplasm

The structure of the cell that consist of all the cellular contents between plasma, membrane, and nucleus

Water, proteins, carbohydrates, lipids, and inorganic substances

What is the cytosol composed of?

Glycolysis

What is an example of a metabolic reaction that occurs in the cytosol?

Inclusions

Aggregations of organic molecules, such as fat or carbohydrates; insoluble, suspended in cytosol, and are not surrounded by a membrane; may appear and disappear, depending on the metabolic needs of the cell

lipid droplets and glycogen granules

what are two examples of inclusions?

Lipid droplets

Contain hydrophobic triglycerides, found in fat cells

Glycogen granules

An aggregation of glycogen molecules found in liver or skeletal muscles

Cytoskeleton

A network of protein, tubules, and filaments that provide structural framework/support for the cell

Microfilaments (5nm to 7nm), intermediate filaments (10nm to 12nm), and microtubules (22nm to 24nm)

What three things does the cytoskeleton consist of

Microfilaments

Thread like protein filaments formed by protein actin; function in movement, periphery structural support, and form the core of microvilli

Intermediate filaments

Strong rope like protein, filaments that provides structural support and anchor organelles; several different proteins can form them; " tonofilaments" of desmosomes

Microtubules

Long unbranched, hollow tubules, composed of the protein tubulin; grow out from an organizing center called the centrosome in non-dividing cells

Microtubules

What functions as an assist of microfilaments in maintaining cell shape and structure

Microtubules

What functions as the intracellular transport of a organelles?

Microtubules

What allows the migration of chromosomes during mitotic spindle cell division?

Microtubules

What forms the core of the cilia and flagella in the framework of centrioles

Centrosome

An organelle located near the nucleus; consisting of a pair of centrioles surrounded by pericentral material

Centrosome

The organelle that serves as an organizing center for the formation of microtubules and non-dividing cells in mitotic spindle and dividing cells

Centrioles

Non-membrane limited cylindrical organelles that have the 9+0 arrangement of microtubule triplets with none in the center

Cilia

Short hair like projections of the plasma membrane; there are many per cell and they are motile

Cilia

Contains a core of 20 microtubules (axoneme) surrounded by the plasma membrane; 9 + 2 arrangement of microtubules; anchored to a basal body

To move materials across the cell surface

What is the function of cilia?

Flagella

An organelle that has a similar structure to cilia; usually one per cell; propels the entire cell; very long

Ribosome

Organelle formed by ribosomal RNA and ribosomal proteins; consists of a small and large sub unit

Nucleolus; cytoplasm

Where are the small and large subunits of the ribosomes made and where do they join together?

Ribosomes

What is the site of protein synthesis?

Free (unattached) and attached

What are the two forms of ribosomes?

The cytoplasm; synthesizes proteins used within the cell

Where does the free ribosome form and what does it do?

Attached to the outer surface of nuclear membrane or to RER; synthesize, integral, membrane, proteins, secretory proteins, or destined for specific organelles

Where are the attached ribosomes attached to and what do they do?

Polyribosomes

Several ribosomes attached to the same messenger RNA

Endoplasmic reticulum

The network of flattened membranous sacs or tubules

Rough endoplasmic reticulum

The endoplasmic reticulum that has that ribosomes on the outer surface; functions in synthesis of secretory proteins, membrane, proteins, and many organelle proteins

Smooth endoplasmic reticulum

The endoplasmic reticulum that extends from the rough ER and no ribosomes are attached to its outer surface

Fatty acids and steroids

What does the smooth endoplasmic reticulum synthesize?

Smooth endoplasmic reticulum

Which endoplasmic reticulum Stores and releases calcium ions; removes the phosphate group glucose-6-phosphate and releases the resulting glucose into the bloodstream; or detoxifies lipids, soluble, drugs, and harmful substances; membrane formation

Golgi complex/apparatus

What is the organelle that consists of a series of flattened membranous sacs?

Cis face

What is the cisterna on the Golgi that faces the rough ER; entry face

Medial cisternae

What is the cisternae on the Golgi between the cis and trans face

Trans face

The cisternae on the Golgi that faces the plasma membrane; exit face

Golgi complex

What organelle receives newly synthesized proteins from the rough ER via transport vesicles, perform modifications on them, and sorts/packages them into vehicles for transport to their final destinations

The extracellular environment; taken by secretory vesicles

Where do secretary proteins go from the Golgi complex?

Taken to the plasma membrane by membrane vesicles

Where are the membrane proteins taken from the Golgi complex?

Lysosomal enzymes taken to lysosomes by transport vesicles

Where are the organelle proteins taken from the Golgi complex?

Lysosomes

The intracellular membrane-enclosed vesicles formed by the Golgi complex

Digestive enzymes

What lysosomes contain that function in digestion

Heterophagy

Digestion of phagocytosed extracellular materials

Autophagy

Digestion of intracellular organelles

Autolysis

Cellular self digestion

Perioxysomes

Organelles that are similar in structure to lysosomes, but smaller; contain oxidative enzymes (oxidases)

Hydrogen peroxide

What is the toxic byproduct that is produced when oxidases remove hydrogen atoms from various organic substances?

Catalase

What is the enzyme that oxidizes, toxic, hydrogen peroxide to water and oxygen?

Mitochondria

The organelle that has a double membrane and is spherical to filamentous organelles

The outer membrane is smooth, and the inner membrane is arranged in a series of folds (mitochondrial cristae); the cristae is studded with elementary particles that contain enzymes for oxidative phosphorylation

Explain the double membrane of the mitochondria

Mitochondrial matrix

The central fluid filled cavity, enclosed by the inner mitochondrial membrane of the mitochondria

DNA, RNA, ribosomes, mitochondrial granules of calcium and magnesium

What four things are within the mitochondrial matrix

Mitochondria

The organelle that generates high energy compounds of ATP and plays an important early role in apoptosis

Apoptosis

What is an orderly, genetically programmed death of a cell

Nucleus

The prominent intracellular organelle in a cell

DNA

What does the nucleus contain?

DNA

The hereditary material in humans and almost all other organisms

nuclear envelope

What is the double membrane of the nucleus called

Genes

The hereditary units of a cell made up of a stretch of DNA that direct the production of proteins