Overview of Prokaryotic Cells, Viruses, and Stem Cells, Biology 142 Exam III Study Guide

Cytoplasm

Viscous material filling the cell volume.

Ribosome

Cellular structures that synthesize proteins.

Cell Membrane

Semi-permeable barrier enclosing cell contents.

Lipid Bilayer

Two-layered structure forming cell membrane.

Periplasmic Space

Gap between cell membrane and cell wall.

Cell Wall

Protective layer outside the cell membrane.

Gram Positive Cell Wall

Thick peptidoglycan layer with teichoic acids.

Gram Negative Cell Wall

Thin peptidoglycan with an outer membrane.

LPS Layer

Lipopolysaccharide layer aiding immune evasion.

Porin Proteins

Transport channels in Gram-negative outer membrane.

Binary Fission

Asexual reproduction method in bacteria.

Lytic Cycle

Viral cycle immediately taking over host cells.

Lysogenic Cycle

Viral cycle hiding in host cell chromosome.

Spongiform Encephalopathies

Brain diseases caused by abnormal prion proteins.

Cell Cycle

Process of cell content duplication and division.

Cyclin-dependent Kinase (Cdk)

Enzyme active only when bound to cyclin.

Cyclin

Protein that regulates Cdk activity throughout cycle.

Checkpoint Mechanism

Controls progression based on cellular criteria.

Restriction Checkpoint

Primary checkpoint assessing cell size and environment.

G2 Checkpoint

Checks chromosome replication before mitosis.

DNA Damage Checkpoint

Halts cycle if DNA damage exceeds threshold.

Chromosome Packaging Levels

Hierarchy of DNA organization from helix to chromosome.

Cytokinesis

Division of cytoplasm following mitosis.

Embryonic Stem Cells

Totipotent or pluripotent cells from early embryos.

Non-Embryonic Stem Cells

Adult stem cells with limited differentiation potential.

Induced Pluripotent Stem Cells

Differentiated cells reverted to pluripotent state.

Differentiation Process

Maturation of cells into specialized types.

Hayflick Limit

Maximum mitotic divisions for somatic cells.

S Phase

Phase where DNA replication occurs before mitosis.

Cdc 20 Complex

Regulates transition from metaphase to anaphase.

Actin Fibers

Contractile structures involved in cytokinesis.

Regenerative Medicine

Uses stem cells to replace damaged tissues.

Stem Cells

Undifferentiated cells capable of developing into various cell types.

Type I Diabetes

Autoimmune condition destroying insulin-producing pancreatic cells.

Parkinson's Disease

Neurodegenerative disorder affecting movement and coordination.

Traumatic Spinal Cord Injury

Damage to spinal cord resulting in loss of function.

Blood Cancers

Cancers affecting blood cells, like leukemia and lymphoma.

Natural Regeneration

Ability to restore damaged tissues, seen in salamanders.

Salamanders

Amphibians capable of complete limb and organ regeneration.

Scar Tissue

Fibrous tissue replacing normal tissue after injury.

Hepatocytes

Liver cells with stem-cell-like regenerative properties.

Stem Cell Collection

Gathering stem cells from various sources for treatment.

Cell Expansion

Increasing stem cell numbers through cell culture techniques.

Scaffold Generation

Creating a structure for cell growth and tissue formation.

Stem Cell Seeding

Placing stem cells on scaffolds for tissue engineering.

Tissue Assessment

Evaluating the functionality of regenerated tissues.

Implantation

Introducing regenerated tissue into a patient's body.

In-Situ Regeneration

Stimulating tissue repair using chemicals at injury site.

Proto-oncogenes

Genes that promote cell division; can become oncogenes.

Tumor Suppressor Genes

Genes that inhibit cell division; mutations can lead to cancer.

DNA Repair Genes

Genes coding for proteins that fix DNA errors.

Cancer Grading

Assessment of cell abnormality in cancerous tissues.

Cancer Staging

Determines extent of tumor spread in the body.

Traditional Cancer Treatments

Include surgery and chemotherapy targeting rapidly dividing cells.

Targeted Cancer Therapies

Treatments that directly target cancer cell mechanisms.

JAX Program

Innovative research approach for personalized cancer treatment.

Nucleoid

The region in a prokaryotic cell where the genetic material is located.

Cytosol

The fluid component of the cytoplasm, excluding organelles and other insoluble components.

Chromosome

A structure composed of DNA and protein that carries genetic information.

Plasmid

A small, circular piece of DNA that is separate from chromosomal DNA and can replicate independently.

Ribosomes

Molecular machines that synthesize proteins by translating messenger RNA.

Cell membrane

A lipid bilayer that surrounds the cell and controls the movement of substances in and out.

Hopanoid

A type of lipid found in some bacterial membranes that helps to stabilize the membrane.

Periplasm

The space between the inner and outer membranes in Gram-negative bacteria.

Cell wall

A rigid structure that provides support and protection to bacterial cells.

Gram +

Bacteria that have a thick peptidoglycan layer in their cell wall and retain the crystal violet stain.

Peptidoglycan

A polymer that makes up the cell wall of bacteria, consisting of sugars and amino acids.

NAM

N-acetylmuramic acid, a component of the peptidoglycan layer in bacterial cell walls.

NAG

N-acetylglucosamine, a sugar that is part of the peptidoglycan structure in bacterial cell walls.

Peptide crosslinks

Connections between peptide chains that provide structural integrity to the peptidoglycan layer.

Teichoic acid

Polymers found in the cell wall of Gram-positive bacteria that play a role in cell wall maintenance and enlargement.

Lipoteichoic acid

A type of teichoic acid that is anchored to the cell membrane and extends through the cell wall.

Gram -

Bacteria that have a thin peptidoglycan layer and an outer membrane, which does not retain the crystal violet stain.

Asymmetric bilayer

A membrane structure where the two layers of phospholipids have different compositions.

Porin proteins

Proteins that form channels in the outer membrane of Gram-negative bacteria, allowing the passage of small molecules.

Flagella

Long, whip-like structures that provide motility to bacterial cells.

Pilus

A hair-like structure on the surface of bacteria that helps in attachment and conjugation.

Fimbriae

Short, bristle-like fibers on bacteria that aid in adherence to surfaces.

Capsule

A thick protective layer surrounding some bacteria, aiding in evasion of the immune system.

Braun's lipoproteins

Proteins that connect the outer membrane to the peptidoglycan layer in Gram-negative bacteria.

LPS

Lipopolysaccharide, a major component of the outer membrane of Gram-negative bacteria that can trigger immune responses.

Virus

A microscopic infectious agent that can only replicate inside the living cells of an organism.

Protein coat

The protective outer layer of a virus, composed of protein subunits called capsomers.

Nucleic acid

The genetic material of a virus, which can be DNA or RNA.

Core

The central part of a virus containing the nucleic acid and associated proteins.

Envelope

A lipid membrane surrounding some viruses, derived from the host cell membrane.

Lytic cycle

A viral replication process that results in the destruction of the host cell.

Virulent

Referring to a virus that causes disease and can lead to the death of the host cell.

Lysogenic cycle

A viral replication process where the viral DNA integrates into the host genome and replicates with it.

Temperate

Referring to a virus that can enter a lysogenic cycle and remain dormant in the host cell.

Prion

An infectious agent composed of protein that can cause neurodegenerative diseases.

vCJD

Variant Creutzfeldt-Jakob Disease, a prion disease linked to consumption of infected beef.

Scrapie

A prion disease affecting sheep and goats, characterized by itching and neurological symptoms.

Bovine Spongiform Encephalopathy

A prion disease in cattle, commonly known as mad cow disease.

PrPC

The normal cellular form of the prion protein.

PrPSC

The misfolded, pathogenic form of the prion protein that causes disease.

Cell cycle

The series of phases that a cell goes through in order to divide and replicate.

G1 phase

The first phase of the cell cycle where the cell grows and prepares for DNA replication.

S/G2 phase

The phase of the cell cycle where DNA is replicated and the cell prepares for mitosis.

M phase

The phase of the cell cycle where mitosis occurs, resulting in cell division.