Human Cell Structure and Function

Flashcards based on key terms and concepts derived from the lecture notes on human cell structure, cell function, and the processes of gene expression.

Cell

The basic unit of life that performs all vital physiological functions.

Organelle

Specialized structures within a cell that perform specific tasks.

Plasma membrane

A selective barrier that separates the cell's interior from its external environment.

Nucleus

The organelle that contains the cell's genetic material (DNA).

Ribosome

Cellular structures responsible for synthesizing proteins.

Mitochondrion

An organelle that produces ATP, the cell's energy currency.

Endoplasmic reticulum

An organelle responsible for synthesizing proteins and lipids; exists in rough (with ribosomes) and smooth forms.

Golgi apparatus

An organelle that modifies, sorts, and packages proteins and lipids for delivery.

Lysosome

A vesicle containing enzymes that digest cellular waste and recycling material.

Cytoskeleton

A network of protein filaments that provide structural support and movement to cells.

Diffusion

The process by which molecules move from an area of high concentration to an area of low concentration.

Osmosis

The movement of water across a selectively permeable membrane from a region of lower solute concentration to one of higher solute concentration.

Active transport

The process that requires energy (ATP) to move substances against their concentration gradient.

Cell division

The process by which a parent cell divides to produce two or more daughter cells.

Mitosis

A type of cell division that results in two genetically identical daughter cells.

Meiosis

A type of cell division that reduces the chromosome number by half, resulting in four genetically varied gametes.

Gene expression

The process by which information from a gene is used to synthesize a functional gene product, typically proteins.

Transcription

The process of copying DNA into messenger RNA (mRNA).

Translation

The process in which ribosomes create proteins based on the sequence of the mRNA.