Cytology and Cell Biology

Flashcards covering cytology, cell theory, organelle functions, membrane structure, and cell division mechanisms based on lecture notes.

Cytology

The study of cell structure and function.

Cell Theory

The principle stating that every living organism is made of cells, cells are the basic structural and functional unit of all living things, cells arise from division of preexisting cells, all cells have the same chemical composition, and functions arise from cellular activity.

Metabolism

Internal chemical change, nearly all of which occurs within cells.

Homeostasis

The maintenance of a stable internal environment.

Responsiveness

The ability of an organism to react to stimuli.

Growth & Development

The process of change from one state or stage to another in living organisms.

Reproduction

The process by which organisms make copies of themselves.

Squamous

Cell shape found in the outer skin.

Cuboidal

Cell shape found on organ surfaces.

Columnar

Cell shape that lines the respiratory tract.

Stellate

Star-like cell shape found in the brain and spinal cord.

Spheroidal

Round cell shape characteristic of white blood cells (WBC).

Discoidal

Disc-shaped cell characteristic of red blood cells (RBC).

Fusiform

Spindle-shaped cell with tapered ends characteristic of smooth muscle.

Fibrous

Thread-like cell shape characteristic of skeletal muscle.

Basic Components of a Cell

Cell membrane, glycocalyx and extensions of the cell membrane, cytosol and cytoskeleton, and organelles.

Plasma (Cell Membrane)

Structure that forms the cell boundary and contains lipids and proteins.

Cytosol

All intracellular fluid; a clear, viscous fluid that bathes the cytoskeleton and organelles.

Extracellular Fluid (ECF)

Fluid not contained in cells.

Interstitial Fluid

Extracellular fluid (ECF) located specifically between cells.

Blood Plasma

An example of extracellular fluid (ECF).

Lymph

An example of extracellular fluid (ECF).

Cerebrospinal Fluid

An example of extracellular fluid (ECF).

Selectively Permeable

Property of the cell membrane that only lets some substances pass.

Intracellular Face

The side of the cell membrane facing the cytoplasm.

Extracellular Face

The side of the cell membrane facing outward.

Phospholipids

Membrane lipids making up about 75% of total membrane lipids, possessing hydrophobic tails and hydrophilic heads.

Hydrophobic Tails

Tails of membrane phospholipids that face inward.

Hydrophilic Heads

Heads of membrane phospholipids that face outward.

Cholesterol

Lipid making up 20% of membrane lipids that can stiffen the membrane.

Glycolipids

Phospholipids with short carbohydrate chains bound to them, making up the remaining 5% of membrane lipids and contributing to the glycocalyx.

Transmembrane Proteins

Membrane proteins, most of which are glycoproteins with carbohydrate chains, that span the membrane.

Peripheral Proteins

Proteins that adhere to the inner or outer face of the cell membrane.

Receptor

Membrane protein that binds chemical signals that trigger a response.

Enzymes

Proteins that carry out chemical reactions at the cell surface.

Channel

Membrane structure that forms channels allowing water and hydrophilic solutes to pass through.

Cell Identity Marker

Structure that serves as identification tags for the cell.

Cell Adhesion Molecule

Membrane protein that allows cells to adhere to each other.

Glycocalyx

Fuzzy surface coat of sugars that protects cells and assists in cell recognition.

Microvilli

Extensions of the cell membrane that increase surface area and appear as a fuzzy brush border.

Brush Border

The fuzzy appearance created by microvilli on the cell membrane.

Cilia

Hair-like processes 7 to 10 µm long on the surface of many cells.

Flagella

Cell processes where the only functional example is the whiplike tail of sperm.

Cytoskeleton

Network of protein filaments within the cell.

Nucleus

Largest organelle in the cell; contains cell chromosomes.

Chromosomes

Structures containing genetic material housed within the nucleus.

Endoplasmic Reticulum

Interconnected channels enclosed by a membrane.

Rough ER

Endoplasmic reticulum covered with ribosomes that produces lipids and proteins.

Smooth ER

Endoplasmic reticulum lacking ribosomes that synthesizes steroids and lipids and detoxifies alcohol and drugs.

Ribosomes

Lineworkers/assemblers that read genetic material and assemble amino acids into proteins.

Golgi Complex

Packing center of the cell that sorts, edits, and packages cell products into golgi vesicles.

Golgi Vesicles

Vessels into which the Golgi complex packages sorted and edited cell products.

Proteasomes

Protein-degrading structures that unwind and break down proteins into amino acids.

Lysosomes

Normal garbage disposal of the cell.

Autophagy

The lysosomal breakdown of extra or aged organelles.

Apoptosis

Programmed cell death.

Peroxisomes

Toxic garbage disposal organelles that break down fatty acids.

Mitochondria

Organelle known as the powerhouse of the cell.

Centrioles

Cylindric assembly of microtubules.

Inclusions

Cellular structures that accumulate cell products.

Tumor (Neoplasm)

Mass of tissue produced when the rate of cell division exceeds cell death.

Malignant Tumor

Tumor that lacks a confining capsule, allowing cells to break free.

Mitosis

Mechanism of cell division for all cells.

Preexisting Cells

The source from which all cells arise according to cell theory.

Chemical Composition of Cells

Principle of cell theory stating that all cells share the same chemical composition.

Cellular Activity

The underlying source from which all functions of living organisms arise.

Location of Metabolism

Nearly all metabolic activity occurs within cells.

Phospholipid Percentage

Phospholipids constitute about 75% of total membrane lipids.

Cholesterol Percentage

Cholesterol constitutes 20% of total membrane lipids.

Glycolipid Percentage

Glycolipids constitute the remaining 5% of membrane lipids.

Stiffening Membrane Lipid

Cholesterol, which functions to stiffen the cell membrane.

Glycolipid Composition

Phospholipids with short carbohydrate chains bound to them.

Transmembrane Glycoproteins

Transmembrane proteins associated with carbohydrate chains.

Peripheral Protein Attachment

Peripheral proteins adhere strictly to either the inner or outer face of the membrane.

Receptor Function

Binds chemical signals to trigger a cellular response.

Surface Enzymatic Reactions

Chemical reactions carried out at the cell surface by enzymes.

Channel Solute Transport

Allows water and hydrophilic solutes to pass through the cell membrane.

Cell Recognition Tags

Function provided by cell identity markers.

Cellular Adhesion Function

Function provided by cell adhesion molecules allowing cells to stick together.

Glycocalyx Functions

Protects cells and assists in cell recognition.

Microvilli Function

Increases the surface area of the cell membrane.

Length of Cilia

7 to 10 µm long.

Sperm Tail

The single functional flagellum found in human cells, exhibiting a whiplike structure.

Cytosol Appearance

Clear and viscous.

Contents of Nucleus

Contains cell chromosomes.

Rough ER Ribosomes

Ribosomes covering the rough ER that participate in producing lipids and proteins.

Smooth ER Ribosome Absence

Smooth ER is characterized by lacking ribosomes on its surface.

Steroid and Lipid Synthesis

Functions carried out by the smooth ER.

Alcohol and Drug Detoxification

Function carried out by the smooth ER.

Ribosome Role

Reads genetic material and assembles amino acids into proteins.

Protein Assembly

The process of joining amino acids into proteins carried out by ribosomes.

Golgi Complex Role

Functions as the cell's packing center.

Golgi Processing Steps

Sorts, edits, and packages cell products into golgi vesicles.

Proteasome Degradation

Unwinds and breaks down proteins into free amino acids.

Garbage Disposal: Normal

Lysosomes.

Garbage Disposal: Toxic

Peroxisomes.

Peroxisome Function

Breaks down fatty acids.

Powerhouse of the Cell

Mitochondria.

Tumor Cause

Imbalance where the rate of cell division exceeds the rate of cell death.