Unit 2

Parts of the cell ect

Semi autonomous system

System that includes the mitochondria and chloroplasts

Cytosol system

The system that includes the cytoskeleton, and cytoplasm

Endomembrane System

The system that includes the nuclear envelope, ER, Golgi apparatus, lysosomes, vacuoles, and peroxisomes.

Nucleus system

The system that contains chromatin, nuclear matrix, chromosomes, nuclear lamina, nucleolus, nuclear pores, and the nuclear pore complex.

Cytoskeleton

System found in cytosol, nucleus, and inner membrane that is made from proteins monomers and filaments.

Microtubules

Filament made from tubulin alpha and beta proteins that are 25 nm in diameter, hollow with a positive and negative end.

Intermediate filaments

Filament made from keratin, lamin, and other proteins that are 10 nm in diameter. They are twisted like a rope and don’t change length.

Actin filaments

Filaments made from actin proteins and are 7 nm in diameter. They are two intertwined strands that can grow rapidly on the + end.

Pseudopodia

Temporary finger-like projections of the plasma membrane that move the cell around an engulf particles.

Functions of Microtubules

Maintain cell shape, and organize and move chromosomes during mitosis, organize organelles, and move cargo.

Functions of Intermediate filaments

Provide mechanical strength and anchor down organelles.

Functions of Actin Filaments

Play a key role in cell shape and strength, support the plasma membrane, create pseudopodia, facilitate movement of cells, move cargo, and muscle contraction.

Microtubule-Organizing Center (MTOC)

Site in eukaryotic cells where microtubules grow.

Motor proteins

Proteins that interact with cytoskeletal filaments to promote movement. These use ATP for energy in their function. Consist of a head, hinge, and tail. The hinge and tail make up the lever arm.

Centrosome

A single MTOC found in nondividing animal cells found near the nucleus.

Dynamic instability

When a microtubule oscillates between growing and shortening phases. Important for sorting chromosomes during cell division.

Centrioles

A pair of structures within the centrosome of animal cells. Most plant cells and many protists lack these.

Axoneme

An internal structure of eukaryotic flagella and cilia that contains microtubules, the motor protein dynein, and linking proteins. Is made of doublet microtubules.

Flagella

Longer usually alone structures that consist of motor proteins and microtubules. They facilitate the movement of cells.

Cilia

Many short structures that consist of motor proteins and microtubules. They facilitate the movement of cells.

Basal body

The “assembly site” where microtubules grow in flegella and cilia. Is a triple structure with 3 microtubules.

Function of Cytosol

The function where metabolic activities take place.

Metabolism

The sum of the chemical reactions that sustain life.

Catabolism

A metabolic pathway that break molecules into smaller components. (Create energy to make building blocks for macromolecules.)

Anabolism

A metabolic pathway that uses energy to build larger molecules. (Polysaccharides, polypeptides, ect.)

Enzyme

A protein that accelerates the rate of a chemical reaction.

Cytoplasm

The whole area inside of the plasma membrane.

Cytosol

A section of cytoplasm that is 85% water, and the rest is vitamins, minerals, and proteins (Cytoskeleton).

Vitamins

Organic molecules that help enzymes.

Minerals

Electrolytes in the cytoplasm that regulate water.

Nuclear Envelope

A double-membrane structure that encloses the cell’s nucleus.

Nuclear Pores

Passageways for the movement of molecules and macromolecules into and out of the nucleus.

Nuclear Pore Complex

Inside the nuclear pores that allow for the movement on molecules in and out of the nucleus.

Chromosome

A discrete unit of genetic material composed of DNA and associated proteins.

Chromatin

Complex of DNA and proteins inside the nucleus.

The Nuclear Matrix

A filamentous network of proteins that is found inside the nucleus and lines the inner nuclear membrane. Keeps chromosomes organized.

Nuclear Lamina

A collection of protein fibers that line the inner nuclear membrane; part of the nuclear matrix.

Nucleolus

A droplet organelle in the nucleus of nondividing cells where ribosome assembly occurs.

Chromosome Territory

A distinct area where each chromosome is located within the cell nucleus of eukaryotic cells.

Functions of the Nucleus

Protection, organization, replication, expression of genetic material, and assembly of ribosomal subunits.

Endoplasm Reticulum

A convoluted network of membranes in a cell’s cytoplasm that forms flattened, fluid-filled tubules, or cisternae.

Lumen

The internal space or hollow cavity of an organelle or an organ, such as the endoplasmic reticulum, the stomach, or a blood vessel.

ER Lumen

A single compartment enclosed by the ER membrane.

Functions of the Rough ER

Sorting of proteins destined for the ER, Golgi Apparatus, Lysosomes, vacuoles, Plasma membrane, and extracellular environment. Also sorting created proteins into the ER membrane, and Glycosylation.

Functions of the Smooth ER

Metabolism (detoxing harmful substances)(Processes glycogen into glucose), storage of Ca2+ ions, and the synthetization of lipids (creating phospholipids, and modifying cholesterol into steroids).

Membrane Vesicles

A small sphere enclosed by a membrane.

Glycosylation

The covalent bond of carbohydrate (sugar) chains to proteins inside the ER or Golgi to ensure proper targeting. (The Destination Passport Stamp / Shipping Barcode)

Functions of the Golgi Apparatus

Processing, protein sorting, and secretion.

Cis face

The receiving doc of the Golgi apparatus. Located closes to the ER and

Secretory Pathway

The continuous chronological highway a protein travels to leave the cell: Rough ER > Vesicle> Golgi > Vesicle > Plasma Membrane. (The International Flight Itinerary) (Think of the layovers).

Pulse-Chase experiment

Experiment where radioactive amino acids were consumed by a cell (Pulse), and pictures were taken every couple of minutes (Chase).

Secretory Vesicles

Tiny membrane-bound bubbles that pinch off the trans Golgi to transport fully finished proteins directly to the plasma membrane for release. (The Outbound FedEx Delivery Trucks). (Sponge bob oozing close up shot)

Proteolysis

A processing event in which enzymes called proteases (Tiny Sukanas) cleave and dismantle specific amino acid sequences in precursor polypeptides to convert them into functional proteins (e.g., converting proinsulin to insulin).

Lysosomes

An organelle in animal cells that break down molecules and macromolecules.

Acid Hydrolases

A hydrolytic enzyme found in lysosomes that functions at acidic pH and uses a molecule of water to break a covalent bond. Solution gets neutralized when exposed to the cells neutral cytoplasm. (Collapsing Star Roaring Cannon neutralized by serious punch).

Autophagy

A degradation pathway where a cell sequesters its own damaged organelles within a double-membrane vesicle (autophagosome) and fuses with a lysosome to recycle the molecular components. (Self-Cannibalism / Dismantling Scrap Metal to Rebuild cars)

Vacuoles

Hold solids and fluids. Usually made of many smaller versions of itself. Radiation Connection: In radiation oncology, large radiation doses can trigger vacuolation (formation of prominent, abnormal cytoplasmic vacuoles) in irradiated cells—a hallmark structural indicator of severe cellular stress and impending necrosis/senescence. (Tojis bug pet that he pulls weapons from).

Central Vacuole

An organelle that often occupies 80% or more of the volume of a plant cell and stores a large amount of water, enzymes, and inorganic ions. (Really fat Toji bug pet).

Turgor Pressure

Something the central vacuole in a plant provides to prevent plants from wilting. Also allows for plant wall growth.

Contractile Vacuole

A place for paramecia to temporarily store water. (Osmoregulation).

Phagocytic Vacuoles

A type of Vacuole that hold onto bacteria that the immune system grabbed. This vacuole then joins with the lysosomes.

Peroxisomes

Organelle that catalyzes hydrogen peroxide. They are found often in the liver cells. Radiation connection: Peroxisomes are easily overwhelmed with all the toxic free radicals to break down. Cancer cells however are smart and will often build many more peroxisomes to make the cell more radiation resistant.

Membrane transport

Movement of ions or molecules across the lipid bilayer.

Cell signaling

Cell membranes contain receptors that they can use to signal one another.

Cell adhesion

Proteins in the plasma membrane that stick together. (Double sided tape).

Mitochondria

Cells have hundreds to thousands of these. Regular exercise increases the number of these in muscle cells. Radiation connection: A major target of radiation therapy, the outer membrane is broken causing apoptosis.

Intermembrane Space (Mitochondria)

The fluid-filled region between the outer and inner mitochondrial membranes that stores accumulated protons (H+) during the electron transport chain and harbors pro-apoptotic proteins like Cytochrome c. Radiation Connection: Radiotherapy causes MOMP (Mitochondrial Outer Membrane Permeabilization), allowing Cytochrome c stored in this space to leak into the cytosol and activate caspase cascades.

Cristae

Infoldings of the inner mitochondrial membrane that drastically increase surface area, housing electron transport chain complexes and ATP synthase for maximum ATP production. Radiation Connection: Radiation causes structural cristae swelling and loss of folding integrity (mitochondrial vacuolation), crippling the cell's ability to maintain ATP synthesis under oxidative stress. (Vagana lol).

Mitochondrial Matrix

A compartment enclosed by the inner membrane of a mitochondrion.

Functions of the Mitochondria

Convert organic molecules such as Glucose into a form that can be used by cells. This is known as cellular respiration. In mutations of this organelle, high energy needing tissues such as neural or muscle cells are affected.

Chloroplasts

Consist of three membranes. The outer membrane, inner membrane, and the thylakoid membrane.

Thylakoid Membrane

A fluid-filled, highly folded 3rd membrane inside chloroplasts that forms flattened tubules.

Granum

A stacked tower of flattened thylakoid discs (Lumen) inside a chloroplast designed to maximize light absorption. (Stacks of pancakes).

Stroma

The fluid-filled region of the chloroplast between the thylakoid membrane and the inner membrane. (Cytoplasm of the chloroplast).

Plastid

What a chloroplast is.

Binary Fission

This is the process that happens to Chloroplasts and Mitochondria to split into two.

Endosymbiosis

A symbiotic relationship in which the smaller species (the symbiont or endosymbiont) lives inside the larger species (the host).

(Venom).

Endosymbiosis Theory

Mitochondria and chloroplasts originated from bacteria that took up residence within primordial eukaryotic cells.