Methods of Studying Cells and Cell Fractionation

The process of separating different components of a cell, such as organelles, for individual study.

A specialized type of centrifugation used to separate cell components based on their density and size, often used in cell fractionation.

A mixture of broken cells and their contents created by blending cells in a homogenizer.

A technique used in cell fractionation where a sample is spun at increasing speeds to sequentially separate organelles based on their density.

The dense material that settles at the bottom of a centrifuge tube during cell fractionation.

The clear liquid that remains at the top of a centrifuge tube after sedimentation, containing lighter cell components.

The control center of a eukaryotic cell, enclosed by a double membrane called the nuclear envelope.

A network of interconnected, flattened membrane-bound sacs involved in protein synthesis and modification.

A double-membraned organelle responsible for cellular respiration, producing energy (ATP) for the cell.

Small, cylindrical structures made of microtubules that play a vital role in cell division by forming spindle fibers that separate chromosomes.

Tiny organelles composed of two subunits (RNA and protein), responsible for protein synthesis.

Vesicles filled with digestive enzymes, breaking down cellular waste and worn-out organelles.

A stage in the cell cycle where the cell grows, prepares for division, and replicates its DNA.

The process of cell division that produces two identical daughter cells, essential for growth and asexual reproduction.

The division of the cytoplasm during cell division, resulting in the formation of two separate daughter cells.

The ability to make new cells through mitosis, contributing to the development and growth of organisms.

The process by which prokaryotic cells divide into two identical daughter cells. It involves DNA replication, cell membrane growth and division of cytoplasm.

A circular molecule of DNA found in prokaryotic cells. It carries essential genetic information for the cell.

Small, circular DNA molecules found in some bacteria and other prokaryotes. They replicate independently of the main DNA molecule.

A barrier that surrounds all cells and organelles. It's made of a phospholipid bilayer with proteins embedded in it.

The arrangement of phospholipids and proteins in the cell membrane. It's called fluid because the components can move and mosaic because it's made of different molecules.

A type of protein that spans the cell membrane, helping specific substances to cross.

Proteins found on the surface of the cell membrane, often involved in cell signaling or attachment.

A type of lipid found on the cell surface containing a carbohydrate molecule. They act as receptors for molecules and help cells recognize each other.

The movement of molecules from an area of high concentration to an area of low concentration, requiring no energy.

The movement of molecules across a membrane from an area of high concentration to an area of low concentration, requiring no energy, but using transport proteins.

A difference in the concentration of a substance between two areas. The steeper the gradient, the faster the rate of diffusion.

Tuberculosis (TB) is caused by the bacterium Mycobacterium tuberculosis. The bacteria infect phagocytes in the lungs and lie dormant inside tubercles, forming hard nodules.

The initial infection with Mycobacterium tuberculosis often goes unnoticed as the bacteria are contained within tubercles.

When the immune system weakens, the bacteria in the tubercles become active and can damage lung tissue, leading to coughing, weight loss, and breathing difficulties.

HIV (Human Immunodeficiency Virus) is a virus that attacks and weakens the immune system.

AIDS (Acquired Immunodeficiency Syndrome) is the final stage of HIV infection, where the immune system is severely compromised, leaving the body vulnerable to infections.

Small, non-polar, lipid-soluble molecules like oxygen and carbon dioxide move through the cell membrane from an area of high concentration to an area of low concentration.

Water molecules move from an area of high water potential to an area of low water potential through a selectively permeable membrane.

This active transport process requires energy to move molecules against their concentration gradient, from an area of low to high concentration.

Large particles are enclosed in vesicles made from the cell membrane and transported into the cell.

Vesicles containing large particles fuse with the cell membrane and release their contents outside the cell.

Ions are used to move other substances across the cell membrane. This is common in the ileum, where sodium and potassium ions are actively pumped out of epithelial cells.

A type of protein in the cell membrane that helps polar and charged molecules cross the membrane.

The outer layer of skin, made of keratin, providing a physical barrier against infection.

A strong acid in the stomach that kills bacteria, preventing infections.

Beneficial bacteria that live on the skin and in the gut, competing with pathogens for resources.

Molecules found on the surface of cells that identify them as self or non-self.

A complex response to injury or infection, characterized by redness, swelling, heat, and pain.

Enzymes present in bodily fluids like tears and mucus, capable of killing bacteria by damaging their cell wall.

Proteins released by infected cells to prevent viruses from spreading to uninfected cells.

A process by which white blood cells engulf and destroy pathogens.