Cell Biology: Nuclear Structure and Function

The basic structural and functional unit of life; the simplest collection of matter that is alive.

The theory stating that all organisms are made up of cells and all cells come from pre-existing cells.

A type of cell that lacks a true nucleus and other membrane-bound organelles.

A type of cell that has a true nucleus and other membrane-bound organelles.

A double layer of phospholipids that forms the outer boundary of a cell, regulating the passage of substances.

The genetic material of a cell, usually found in the nucleus of eukaryotic cells.

Small complexes within cells where protein synthesis takes place.

The semifluid substance within the plasma membrane of a cell.

A non-membrane bound region in prokaryotic cells where DNA is located.

A type of asexual reproduction in prokaryotic cells where DNA is copied and the cell divides into two identical cells.

The nuclear envelope is a double membrane that surrounds the nucleus, separating it from the cytoplasm. It plays a crucial role in controlling the movement of molecules between the nucleus and the cytoplasm.

Each membrane of the nuclear envelope is composed of a lipid bilayer, a double layer of lipids. This structure helps to maintain the integrity of the nucleus and regulate the passage of molecules.

Nuclear pores are channels or openings in the nuclear envelope that allow the selective passage of molecules into and out of the nucleus. They regulate the transport of essential substances like proteins and RNA.

Chromatin is the complex of DNA and proteins that make up the genetic material within the nucleus. It's organized into long strands, allowing for efficient storage and access to genetic information.

The nucleolus is a dense region within the nucleus where ribosomal RNA (rRNA) synthesis occurs. rRNA is essential for the construction of ribosomes, the cellular machinery responsible for protein synthesis.

The nuclear lamina is a network of proteins that lines the inner surface of the nuclear envelope. It provides structural support for the nucleus, helps maintain its shape, and anchors chromatin.

The nuclear envelope is attached to the endoplasmic reticulum (ER), a network of membranes involved in protein synthesis and transport. This connection facilitates the movement of molecules between the nucleus and the ER.

The outer membrane of the nuclear envelope is continuous with the endoplasmic reticulum (ER), further emphasizing the close relationship between these structures.

The nuclear envelope and the ER are essential for the synthesis, processing, and transport of proteins within the cell. They work together to ensure the proper functioning of the cell.

The nuclear pores regulate the entry and exit of molecules from the nucleus, facilitating the flow of genetic information and essential cellular components.

The endoplasmic reticulum (ER) is a network of membranes that extends throughout the cytoplasm of eukaryotic cells. It's involved in the synthesis of lipids and proteins, as well as detoxification and calcium storage.

Smooth ER lacks ribosomes and is involved in the synthesis of lipids, detoxification, and calcium storage in muscle cells.

Rough ER has ribosomes attached to its surface and is involved in the production of proteins.

The Golgi apparatus is a stack of flattened membranous sacs that modifies, sorts, and packages proteins and lipids for secretion or use within the cell.

Lysosomes are membrane-bound organelles containing hydrolytic enzymes that break down cellular waste, worn-out organelles, and ingested substances.

Mitochondria are double-membraned organelles responsible for cellular respiration, which produces ATP, the cell's energy currency.

Chloroplasts are double-membraned organelles found in plants and algae that carry out photosynthesis, the process of converting light energy into chemical energy.

The nuclear envelope, ER, Golgi apparatus, lysosomes, and plasma membrane are all part of the endomembrane system, which works together to modify, package, and transport proteins and lipids within the cell.

Mitochondria and chloroplasts are not part of the endomembrane system, but they are still important organelles with double membranes. They also have their own DNA and produce proteins via ribosomes.

A proton pump in the lysosomal membrane imports protons from the cytosol, using ATP hydrolysis, thereby maintaining the acidic internal pH of the lysosome.

A membranous sac inside a chloroplast where light energy is captured during photosynthesis.

A stack of thylakoids within a chloroplast.

The internal fluid of a chloroplast, surrounding the thylakoids.

Organelles responsible for breaking down fatty acids, alcohol, and protecting cells from reactive oxygen species.

Harmful molecules produced as a byproduct of normal cellular metabolism, radiation, or environmental factors.

A network of protein fibers extending throughout the cytoplasm of a cell, providing structural support, aiding movement, and organizing cellular activities.

The thickest components of the cytoskeleton, involved in cell shape, organelle movement, and cell division.

The thinnest components of the cytoskeleton, involved in cell shape, muscle contraction, and cytoplasmic streaming.

Fibers with diameters between microtubules and microfilaments, involved in providing structural support and maintaining cell shape.

A complex network of molecules outside the plasma membrane of animal cells, providing structural support, cell movement, and cell-to-cell signaling.