AnaPhy - Cells

Cells

Cells

are the structural units of all living things.

Nucleus

control center of the cell; contains genetic material.

Deoxyribonucleic Acid

needed for building proteins, necessary for cell reproduction.

Nuclear Envelope

consists of a double membrane that bounds the nucleus.

Nuclear Pores

allow for exchange of materials with the rest of the cell.

Nucleoplasm

jellylike fluid that encloses the nucleus.

Nucleolus

sites of ribosome assembly; ribosomes migrate into the cytoplasm through nuclear pores to serve as the site of protein synthesis.

Chromatin

scattered throughout the nucleus and present when the cell is not dividing.

Chromosomes

rod-like bodies that form during cell division; comes from the chromatin.

Plasma Membrane

transparent barrier for cell contents; separate cells from surrounding external environment.

Fluid Mosaic Model

constructed of phospholipids that are connected “tail to tail”.

Glycolipids

sugar groups attaching to the phospholipids.

Cholesterol and Protein

scattered around phospholipids.

Hydrophilic Polar “Heads”

are oriented in the inner and outer surface of the membrane.

Hydrophobic Polar “Tails”

are oriented in the center of the membrane.

Proteins

receptors for hormones and other chemical messenger, transport as channels or carriers; responsible for enzymes.

Glycoproteins

are branched sugars attached to proteins that abut extracellular space.

Glycocalyx

is the fuzzy, sticky, sugar-rich area on the cell’s surface.

Tight Junctions

impermeable junctions; binds cell together into leakproof sheets.

Desmosomes

anchoring junctions that prevent cells from being pulled apart as a result of mechanical stress.

Gap Junctions

allow communication between cells.

Cytoplasm

the cellular material outside the nucleus and inside the plasma membrane; site of most cellular activities.

Cytosol

fluid that suspends other elements and contains nutrients and electrolytes.

Inclusions

chemical substances, such as stored nutrients, that float in the cytosol.

Organelles

metabolic machinery of the cell that performs functions for the cell.

Mitochondria

powerhouse of the cell; carry out reactions in which oxygen is used to break down food into ATP molecules.

Ribosomes

made out of protein and rRNA; sites of protein synthesis in the cell.

Endoplasmic Reticulum

fluid-filled tunnels that carry substances within the cells.

Rough Endoplasmic Reticulum

studded with ribosomes; synthesizes proteins; transport vesicles and moves proteins within the cell.

Smooth Endoplasmic Reticulum

lacks ribosomes; functions in lipid metabolism; detoxification of drugs and pesticides.

Golgi Apparatus

appears as a stacked, flattened membranes with tiny vesicles; modifies and packages proteins coming from the rough ER.

Pathway 1

Secretory Vesicles

Pathway 2

In-House Proteins and Lipids

Pathway 3

Lysosomes

Lysosomes

contain digestive enzymes; house phagocytes that dispose of bacteria and cell debris.

Peroxisomes

contain oxidase enzymes; detoxify harmful substances like alcohol and formaldehyde; replicate by pinching in half or budding from the ER.

Cytoskeleton

network of protein structures that extends in the cytoplasm; internal framework of the cell.

Microfilaments

form the blue bat-like network; involved in muscle contractions.

Intermediate Filaments

form the purple network surrounding the pink nucleus; resist mechanical forces acting on the cell.

Microtubules

appear as gold networks surrounding the cell’s pink nuclei; supports the cell and gives its shape.

Centrioles

generate microtubules; direct the formation of mitotic spindle during cell division; storage for nutrients and wastes.

Cilia

moves material across the cell surface; located in the respiratory system to move mucus.

Flagella

propel the cell

Microvilli

increase surface area for absorption; finger-like extensions of the plasma membrane.

Fibroblasts

secrets cable-like fibers.

Erythrocytes

carries oxygen in the blood stream.

Epithelial Cell

packs together in sheets; intermediate fibers resist tearing during rubbing or pulling.

Skeletal Muscle and Smooth Muscle Cells

contractile filaments allows cells to shorten forcefully.

Fat Cells

lipid droplets stored in cytoplasm.

White Blood Cells

digests infectious microorganisms.

Neuron

or nerve cells; receive and transmit messages to other body structures.

Oocytes

largest cell in the body; divides to become an embryo upon fertilization.

Sperms

built for swimming towards the egg cells; flagellum acts as the motile whip.

Solution

homogeneous mixture of two or more components.

Solvent

dissolving medium present in larger quantity.

Solutes

components of smaller quantities in a mixture.

Intracellular Fluid

nucleoplasm and cytosol; solution containing gases, nutrients, and salts dissolved in water.

Extracellular Fluid

interstitial fluid; contains thousands of ingredients.

Passive Process

substances are transported across the membrane without any input from the cell.

Active Process

the cell provides ATP to drive transport process.

Diffusion

molecule movement is from high concentration to low concentration; particles distribute evenly; kinetic energy causes molecules to move randomly.

Simple Diffusion

an unassisted process; solutes are lipid-soluble or small enough to pass through membrane pores.

Osmosis

simple diffusion of water across a selectively permeable membrane.

Isotonic Solutions

have the same solute and water concentrations as cells and cause no visible changes in the cell.

Hypertonic Solutions

contain more solutes than cells do; the cell will begin to shrink.

Hypotonic Solutions

contain less solutes than cells do; the cell will become plump.

Facilitated Diffusion

transports lipid-insoluble and large substance.

Filtration

water and solutes are forced through a membrane by fluid, or hydrostatic, pressure.

Active Transport

amino acids, some sugars, and ions are transported by protein carries called solute pumps.

Sodium-Potassium Pump

necessary for nerve impulses; sodium is transported out of the cell; potassium is transported into the cell.

Vesicular Transport

substances are moved across the membrane in bulk without actually crossing the plasma membrane.

Exocytosis

mechanism cells use to actively secrete hormones, mucus, and other products.

Vesicle

a sac that carries materials and migrates to and combines with the plasma membrane.

Endocytosis

extracellular substances are enclosed in a vesicle; vesicle detaches from the plasma membrane and moves into the cell then fuses with lysosomes.

Phagocytosis

“cell eating”; cell engulfs large particles such as bacteria and dead body cells; a protective mechanism, not a means of getting nutrients.

Pseudopods

are cytoplasmic extensions that separate substances from the external environment.

Pinocytosis

“cell drinking”; cell gulps droplets of extracellular fluid containing dissolved proteins and fats.

Receptor-Mediated Endocytosis

method for taking up specific target molecules.

Cell Life Cycle

is a series of changes the cell experiences from time it is formed until it is divided.

Interphase

or also the metabolic phase; cell grows and it is the longest phase.

Cell Division

cell divides itself.

DNA Replication

genetic material is duplicated and readies the cell for division; occurs towards the end of interphase.

Adenine

Thymine

Guanine

Cytosine

Mitosis

division of the nucleus.

Cytokinesis

division of the cytoplasm; begins during anaphase and ends during telophase.

Prophase

chromatin coils into chromosomes; centromere holds chromatids together; centrioles direct the assembly of mitotic spindle; nucleus envelope and nucleoli have broken down.

Metaphase

chromosomes are aligned at the center of the cell; straight line of chromosomes can be seen.

Anaphase

centromere splits; chromatids move slowly apart.

Telophase

reverse of prophase; chromosomes uncoil to become chromatins, spindles break down and disappear.

Cleavage Furrow

forms to pinch the cells into two parts.

Gene

DNA segment that carries out the blueprint for building one protein or polypeptide chain.

Fibrous Proteins

building materials of cells.

Globular Proteins

can act as enzymes.

RNA

single-stranded; contains ribose sugar and has uracil instead of thymine.

Transfer RNA

transfers appropriate amino acids to the ribosome for building protein.

Ribosomal RNA

helps the ribosomes where the proteins are built.

Messenger RNA

carries the instructions for building a protein from the nucleus to the ribosome.

Transcription

transfer of information from DNA’s base sequence to the complementary base sequence of mRNA.

Translation

base sequence of nucleic acid is translated to amino acid sequence.