Module 3 - Cells And Their Functions

Microscope

Magnifying instrument used to examine cells and structures not visible with the naked eye

Cytology

Study of cells

Compound Light Microscope

Laboratory microscope that uses visible light and lenses to magnify objects up to 1000 times

Transmission Electron Microscope or TEM

High power microscope using electron beams to magnify internal structures up to 1 million times

Scanning Electron Microscope or SEM

Electron microscope that magnifies up to 100000 times to provide three-dimensional surface views

Cilia

Short hairlike projections from cells that move surrounding fluids

Micrometer or mcm

Metric unit of microscopic measurement equal to 1 one-thousandth of a millimeter

Cell Stains

Special dyes applied to cells and tissues to add color and contrast for light microscope viewin

Plasma Membrane

Outer layer of the cell that encloses cell contents and regulates what enters and leaves the cell

Phospholipid Bilayer

Double layer of lipid molecules containing phosphorus that forms the main structure of the plasma membrane

Cholesterol in Membrane

Lipid component interspersed within the phospholipid bilayer that makes the plasma membrane stronger and more flexible

Glycoproteins and Glycolipids

Carbohydrates on the outer membrane surface combined with proteins or lipids that help cells recognize each other and stick together

Channels

Plasma membrane pores that allow specific substances such as ions and water to pass through

Transporters

Membrane proteins that change shape to shuttle substances like glucose across the plasma membrane

Receptors

Specialized membrane proteins that bind chemical signals like hormones or neurotransmitters to alter cell function

Linkers

Membrane proteins that attach to internal proteins to stabilize the membrane or connect to adjacent cells

Cell Identity Markers

Unique surface proteins that identify a person's cells and play a key role in immune function and tissue transplantatio

Organelle

Specialized structure within a cell that performs a specific function

Nucleus

Large membrane-bound organelle that contains chromosomes and directs cellular activities

Chromosome

Hereditary structure located in the nucleus that carries genes and directs cell function

Nucleolus

Small body inside the nucleus that manufactures ribosomes

Cytoplasm

Colloidal material between the nuclear membrane and plasma membrane consisting of cytosol and organelles

Cytosol

Fluid portion of the cytoplasm surrounding organelles where chemical reactions occur

Endoplasmic Reticulum or ER

Network of membranes where rough ER modifies proteins and smooth ER synthesizes lipids

Ribosomes

Small structures composed of RNA and protein that manufacture proteins

Golgi Apparatus

System of folded membranes that modifies sorts and packages proteins for transport

Mitochondria

Large organelles with folded inner membranes that convert nutrient energy into ATP

Lysosomes

Small sacs containing digestive enzymes that break down waste within the cell

Peroxisomes

Membrane-enclosed organelles containing enzymes that break down harmful toxic substances

Proteasomes

Barrel-shaped protein complexes that destroy improperly synthesized or defective proteins

Vesicles

Small membrane-bound sacs that store and move materials into out of or within the cell

Centrioles

Rod-shaped bodies near the nucleus that help separate chromosomes during cell division

Microvilli

Short membrane extensions that function to absorb materials into the cell

Flagellum

Long whiplike extension from the cell surface that moves the cel

Cilia

Microscopic short hairlike projections on the cell surface that move surrounding fluids

Flagellum

Long whiplike extension from a cell used for cell movement or locomotion

Cellular Diversity

Concept that cells vary in size shape and organelle composition to match their specific functions

Neuron Structure

Specialized cell with long fibers designed to transmit electrical signals over long distances

Red Blood Cell Adaptation

Small flexible cell that loses its nucleus and organelles upon maturing to maximize space for oxygen transport

Organelle Abundance

Variation in the number of organelles within a cell based on its functional needs such as abundant mitochondria in active cells or high ER content in secretory cell

Selectively Permeable

Term describing a plasma membrane that regulates which substances can enter or leave the cell

Passive Transport

Movement of substances across the plasma membrane down a gradient without requiring ATP

Diffusion

Net movement of solutes from a region of higher concentration to a region of lower concentration

Osmosis

Passage of water across a semipermeable membrane toward the region of higher solute concentration

Osmotic Pressure

Measure of the force driving water movement or a solution tendency to draw in water

Isotonic Solution

Solution with the same solute concentration as cell fluid resulting in no net movement of water

Normal Saline and Dextrose Values

Clinical isotonic examples consisting of 0 point 9 percent salt or 5 percent glucose

Hypotonic Solution

Solution with a lower solute concentration than cell fluid causing cells to swell

Hemolysis

Bursting of red blood cells caused by water entering when placed in a hypotonic solution

Hypertonic Solution

Solution with a higher solute concentration than cell fluid causing water loss

Crenation

Shrinking or shriveling of cells placed in a hypertonic solutio

Genes

Distinct units of a chromosome that carry genetic instructions and direct protein manufacture in the cell

DNA or Deoxyribonucleic Acid

Double stranded helical nucleic acid in the nucleus that serves as the cell master genetic blueprint

DNA Base Pairing Rules

Adenine pairs with Thymine and Guanine pairs with Cytosine in DNA molecules

RNA or Ribonucleic Acid

Single stranded nucleic acid containing ribose sugar and uracil that carries out protein synthesis

RNA Base Pairing Rules

Adenine pairs with Uracil and Guanine pairs with Cytosine during RNA transcription

Nucleotide Triplet Code

Sequence of three nitrogenous bases in DNA or RNA that codes for a specific amino acid

Mutation

Any change in the DNA sequence of a gene that can alter or stop protein synthesis

Transcription

Process occurring in the nucleus where the genetic code from DNA is copied into messenger RNA

Translation

Process occurring at the ribosome in the cytoplasm where mRNA is decoded to build a protein chain

Messenger RNA or mRNA

RNA molecule that transcribes the DNA code in the nucleus and carries it to the cytoplasm

Ribosomal RNA or rRNA

RNA type that combines with proteins to construct the ribosome structure

Transfer RNA or tRNA

RNA molecule in the cytoplasm that carries specific amino acids to the ribosome during translatio

Mitosis

Type of cell division that produces two daughter cells identical to the parent cell

Interphase

Period of the cell cycle when the cell is active but not actively dividing

Prophase

First stage of mitosis where chromosomes condense centrioles move to opposite ends and the nuclear membrane disappears

Metaphase

Second stage of mitosis where chromosomes line up across the center or equator of the cell

Anaphase

Third stage of mitosis where centromeres split and chromosomes move toward opposite ends of the cell

Telophase

Final stage of mitosis where new nuclear membranes form around separated chromosomes

Daughter Cells

Two new cells produced by mitosis that contain the exact same kind and amount of DNA as the parent cel

Free Radicals or ROS

Harmful substances produced during normal metabolism that can injure cells if not destroyed

Stem Cell Aging

Decline in stem cell division frequency and cell activity that slows down tissue repair in older individuals

Apoptosis

Orderly genetically programmed cell death required for tissue development remodeling and repair

Programmed Cell Division Limit

Theory of aging holding that cells are genetically set to divide only a specific number of times before dying

Suicide Genes

Genes that code for enzymes that quickly destroy a cell during apoptosis without damaging nearby tissue

Metastasize

Process by which cancer cells spread from their original location to other tissues in the body

Carcinogen

Any chemical radiation or substance that causes cancer by damaging cellular DNA

Cancer Risk Factors

Conditions or behaviors that increase disease probability including heredity chemicals radiation obesity physical inactivity poor nutrition and infectious agents

Infectious Cancer Agents

Biological pathogens such as Human Papillomavirus or Helicobacter pylori that promote cancer development

Cyto Root

Meaning cell

Micro Root

Meaning small

Bi Prefix

Meaning two or double

Chromo Root

Meaning color

Endo Prefix

Meaning in within or inside

Lyso Root

Meaning loosening dissolving or separating

Some Suffix

Meaning body or physical structure

Exo Prefix

Meaning outside out of or away from

Hemo Root

Meaning blood

Hyper Prefix

Meaning above over or excessive

Hypo Prefix

Meaning deficient below or beneath

Iso Prefix

Meaning same or equal

Phago Root

Meaning to eat or ingest

Pino Root

Meaning to drink

Semi Prefix

Meaning partial or half

Inter Prefix

Meaning between

Meta Prefix

Meaning change or beyond

Pro Prefix

Meaning before or in front of

Telo Prefix

Meaning end

Carcino Root

Meaning cancer or carcinoma

Gen Suffix

Meaning agent that produces or originate