Tissues and cells

Cell

The simplest unit of life, capable of independent function and growth in a controlled environment.

Tissues

Composed of cells and cell products, working together for a specific function

Squamous Epithelium

Thin, single-layered cells.

Polygonal Cells

Cells with multiple sides.

Cuboidal Cells

Cube-shaped cells.

Columnar Cells

Column-shaped cells.

Spherical Cells

Spherical cells, example: white blood cells.

Discus Cells

Discus-shaped cells, example: red blood cells.

Stellate Cells

Star-shaped cells, example: neurons.

Fusiform Cells

Spindle-shaped cells, thick in the middle, tapered on the ends.

Plasma Membrane

Outer boundary of the cell, visible as a light pink ring under a light microscope.

Nucleus

A prominent intracellular organelle, stained purple in light microscope images, contains DNA.

Cytoplasm

The space between the plasma membrane and the nucleus.

Intracellular

Inside of the cell.

Electron Microscope

Applies a much greater level of magnification resulting in greater resolution

Organelles

Cellular components such as mitochondria, Golgi apparatus, and ribosomes that are smaller.

Cytoskeleton

The cell's skeleton composed of tiny protein fibers that act as the scaffold for the cell to maintain its shape.

Cytosol

The gel within the cell in which organelles are embedded.

Apical Surface

The top surface of a cell.

Basal Cell Surface

The bottom cell surface that is adhered to something.

Intercellular Space

The space between two plasma membranes of adjacent cells.

Phospholipid Bilayer

The basis of the plasma membrane, composed of phospholipids.

Amphiphilic

Having both hydrophobic and hydrophilic parts within its molecular structure

Hydrophilic (Phosphate Head)

Water-loving part, that orient themselves at the interface with intracellular and extracellular fluid.

Hydrophobic (Fatty Acid Tail)

Water-fearing part, away from the fluid and facing one another.

Cholesterol

Lends to what we call membrane fluidity.

Glycolipids

Carbohydrate chains extending off of the extracellular side of the plasma membrane.

Glycocalyx

The sugar coating on the outside of cells, formed by the carbohydrate chains of glycoproteins and glycolipids.

Nonmotile Cilia

Found on nearly every cell, but we don't really understand the purpose of those nonmotile cilia.

Sensory Input Cilia

Sensory input such as taste, odors, even hearing, all require cilia in order for stimuli and such to be processed correctly

Flagella

The longest of all these surface extensions

Endoplasmic Reticulum (ER)

Little network within the cytoplasm.

Rough ER

Covered with ribosomes synthesizes packaged proteins, phospholipids, and proteins of the plasma membrane.

Smooth ER

Lacks ribosomes and synthesizes lipids, steroids, and is involved in detoxification.

Ribosome Function

Amino acids are assembled into proteins.

Golgi Complex

Series of membranous flattened sacs located near the nucleus that package proteins.

Lysosomes

An organelle that is a bag of enzymes.

Lysosome Metabolism

Digest all of our breakdown reactions.

Lysosome Importance

Digesting old organelles within the cell that need to be replaced and initiating apoptosis, the healthy form of cell death.

Peroxisome

Detoxifier, produces hydrogen peroxide.

Mitochondria

The powerhouse organelle.

Centriole

Responsible for cell division.

Cytoskeleton

The cell's little miniskeleton.

Plasma Membrane

Diffusion that's occurring, transport of ions and molecules across both layers of the plasma membrane

Selectively Permeable

Things can be transported in and out, but it's regulated.

Passive Transport

Not ATP utilizing, no energy is required for transport.

Active Transport

Require energy, and they need ATP.

Filtration

Particles being moved through a selectively permeable membrane.

Hydrostatic Pressure

The pressure of the body fluids, whether it's in the cell or outside of the cell, up against the plasma membrane.

Simple Diffusion

Also passive because, again, it doesn't require energy.

Osmosis

Water specific diffusion.

Aquaporins

Water is transported via these specialized protein channels.

Less Free Water

Where there is higher solute concentration.

Driving Osmosis

The tonicity of a solution.

Isotonic

The concentration is the same as what's in the cell.

Hypotonic

There is a smaller concentration than what is in the cell.

Hypertonic

You're placing the cell in a more concentrated solution.

Normal Conditions

Saline solution with the same concentration of electrolytes of salts.

Hypertonic Effect

That cell would be expected to lose water.

Carrier Mediated Transport

Requires a helper or chaperone protein.

Specific Mechanisms

The two types facilitated diffusion or active transport.

Uniporters

They just carry one solute at a time.

Symporters

They can carry two or more at the same time.

Antiporters

Carry two or more solutes but in opposite direction.

Lock and Key

The solute, it binds to the carrier.

Active

Instead of down the concentration gradient, we're moving a substrate against its gradient.

Forms of Transport

Moving a substrate against its gradient, consuming ATP.

Active Transport

Transporting a substrate against its concentration gradient, requiring ATP.

Sodium Potassium Pump

An example of active transport that exchanges three sodium ions out for every two potassium ions in.

Embedded Channel Protein

A channel protein that consumes energy to move substances against their concentration gradient.

Cell Membrane Potential

The imbalance in charge created by the sodium-potassium pump, maintaining a negative charge inside the cell and a positive charge outside.

Uniporter

Transports one type of solute.

Symporter

Transports two or more solutes in the same direction.

Antiporter

Transports two or more solutes in opposite directions.

Exocytosis

Bulk transport out of the cell.

Endocytosis

Bulk transport of substrate into the cell.

Phagocytosis

Cell eating, where a cell takes up large particles and breaks them down.

Pinocytosis

Cell drinking, or uptake of fluid droplets.

Receptor Mediated Endocytosis

Specific endocytosis involving receptors on the cell membrane.

Nucleus

The organelle that serves as the storage site for DNA in the cell.

Histones

Organizing proteins that DNA is associated with in the nucleus.

Chromatin

Collective term for DNA strands along with packing proteins in the nucleus.

Nucleolus/Nucleoli

A concentrated area in the nucleus where ribosomes are made.

Nucleotide

The monomer of nucleic acids, consisting of a phosphate, sugar, and base.

Purines

Double ring bases; adenine (A) and guanine (G).

Pyrimidines

Single ring pyrimidines; cytosine, thiamine, and uracil.

Law of Complementary Base Pairing

The law stating that in DNA, adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G).

Protein Synthesis

The two-step process of protein creation using transcription and translation.

Transcription

The stage that converts genetic information in DNA into messenger RNA (mRNA).

Translation

The process where the information in mRNA is translated into protein, occurring in the ribosomes.

Base Triplet

A set of three nucleotides read at a time, coding for amino acids.

Codon

The mirror image of a base triplet in mRNA form.

Introns

Non-coding sequences that are removed from the initial messenger RNA strand.

Exons

Coding sequences that remain after introns are removed and are translated.

RNA Polymerase

The enzyme responsible for converting DNA into messenger RNA during transcription.

Alternative Splicing

When exons are spliced together in different combinations to produce different proteins.

Ribosomal RNA (rRNA)

RNA molecules that read the messenger RNA strand and assemble amino acids into a final protein.

Transfer RNA (tRNA)

Molecules that deliver the appropriate amino acid to the ribosome for translation.

DNA Polymerase

The enzyme that makes a copy of DNA during DNA replication.

Semiconservative

A DNA copy where the newly synthesized strand forms a helix with the original strand.