Cells and Organelles Lecture

This flashcard set covers the introductory concepts of biology including cell theory, differences between prokaryotic and eukaryotic cells, surface area to volume ratios, and the theory of endosymbiosis.

Cell Theory

The biological principle stating that life is composed of one or more cells, the cell is the basic unit of life, and cells come from reproduction of other cells rather than arising spontaneously.

Binary fission

A specific kind of cell division performed by prokaryotes.

Theory (Biology definition)

A concept that explains a widespread phenomenon across nature and is supported by an overwhelming amount of evidence.

Organelle

A specialized structure inside a cell that performs specific tasks but is not self-sustaining and cannot survive independently.

Cell membrane

A fluid structure that creates a boundary for the cell.

Cytoplasm

A thick, gel-like substance that provides structure and support within the cell.

Ribosomes

Structures responsible for manufacturing proteins.

Genetic material

The DNA within a cell that stores information.

Red blood cells (human)

A unique cell type that starts with DNA but loses it as they mature.

Prokaryotes

Unicellular organisms, specifically Bacteria and Archaea, that lack membrane-bound organelles.

Eukaryotes

Organisms, mostly multicellular like animals, plants, and fungi, whose defining feature is the presence of membrane-bound organelles.

Protists

Unicellular eukaryotic organisms that have membrane-bound organelles but are not descended from a single common ancestor.

Polyphyletic

A term describing organisms, such as protists, that are not descended from a single common ancestor despite having some similarities.

Nucleoid

The non-membrane bound area in a prokaryotic cell where the circular DNA is located.

Flagellum

A tail-like specialized structure that helps a prokaryotic cell move.

Fimbriae

Hair-like structures that help prokaryotic cells attach to surfaces.

Endocytosis

The process where a cell membrane pinches inward to engulf and bring large materials into the cell; eukaryotic cells can do this, but prokaryotic cells cannot.

Surface area

The total area on the outside of a cell or object that creates a boundary.

Volume

Everything located on the inside of a cell or object.

Surface area to volume ratio impact

A ratio that dictates the rate of exchange for gases, nutrients, and waste; a smaller size results in a higher ratio and faster exchange.

Compartmentalization

The use of membrane-bound organelles in eukaryotic cells to group together substrates for specific chemical reactions or separate incompatible reactions by location.

Theory of Endosymbiosis

The theory that some organelles, specifically mitochondria and chloroplasts, evolved from bacteria that were engulfed by and lived inside ancestral archaeal cells.

Alpha proteobacteria

The specific bacterial lineage from which mitochondria are descended.

Cyanobacteria

The specific bacterial lineage from which chloroplasts are descended.

COX1

A gene essential for cellular respiration found in both bacteria and mitochondrial genomes, but not in the nuclear genome.

Symbiotically

A relationship where two organisms need each other to survive, as seen in the amoeba and bacteria experiment.