Cellular Biology, Organelles, and Cell Division Flashcards

Vocabulary practice flashcards generated from lecture notes covering cytoplasm, organelles, nuclear functions, protein synthesis, and cell division mechanics.

Cytoplasm

The cellular material located outside of the nucleus but inside the plasma membrane.

Cytosol

The water-based fluid portion of the cytoplasm containing dissolved molecules, ions, proteins, enzymes, and food.

Cytoskeleton

An internal framework of the cell that provides support, gives structure, allows movement, and deforms during cell division.

Microtubules

Cytoskeletal structures that act as internal scaffolding, assist with cell transport, and organize spindle fibers during cell division.

Microfilaments

Cytoskeletal elements, also known as actin filaments, that provide structure, support microvilli, and help the cell contract.

Organelles

Small, specialized, mostly membrane-bound structures within a cell that perform specific functions.

Nucleus

A large, membrane-bound organelle surrounded by a double membrane with nuclear pores that houses DNA, RNA, and the nucleolus.

Nuclear Pores

Little fused openings in the nuclear double membrane that allow materials to move into and out of the nucleus.

Nucleolus

A dense center located deep inside the nucleus where ribosomes are manufactured.

Chromatin

Disorganized, non-condensed DNA material scattered throughout the cell when it is in its resting or normal phase.

Chromosome

The tightly packaged, organized form of DNA created when chromatin winds up during cell division.

Ribosomes

Organelles responsible for protein synthesis.

Free Ribosomes

Ribosomes floating unattached in the cytoplasm that manufacture proteins used internally by the cell itself.

Rough Endoplasmic Reticulum

A network of folded membranes continuous with the nuclear envelope, studded with ribosomes, that manufactures proteins destined for exocytosis.

Smooth Endoplasmic Reticulum

A network of folded membranes lacking ribosomes that synthesizes lipids and participates in detoxification.

Golgi Apparatus

An organelle composed of flattened membrane sacs that acts as a shipping center to modify, fine-tune, package, and transport proteins and lipids.

Cis Face

The side of the Golgi apparatus located on the same side as the endoplasmic reticulum.

Trans Face

The side of the Golgi apparatus located on the opposite or outer side away from the endoplasmic reticulum.

Lysosomes

Organelles formed at the Golgi apparatus containing hydrolytic enzymes used to break down cellular material, nutrients, or pathogens.

Autophagy

The process of self-eating in which a cell intentionally digests its own damaged, old, or mutated parts.

Peroxisomes

Organelles containing enzymes that digest fatty acids and amino acids, creating toxic hydrogen peroxide, as well as catalase to convert hydrogen peroxide into water and oxygen.

Mitochondria

The powerhouse of the cell where the vast majority of cellular energy ($ATP$) is produced aerobically.

Free Radicals

Dangerous, unbound free electrons spit out during $ATP$ production in the mitochondria that cause cellular damage if oxygen does not bind them.

Transcription

The first step of gene expression in the nucleus where a DNA sequence is copied into messenger RNA ($mRNA$).

mRNA

Messenger RNA; a carbon copy of DNA that leaves the nucleus and travels to a ribosome to provide instructions for protein creation.

Translation

The process at the ribosome where tRNA matches its code to mRNA and deposits amino acids to form a protein chain.

Interphase

The main phase of the cell cycle between divisions where the cell carries out normal functions and replicates its DNA.

Mitosis

The nuclear division of somatic cells that produces two genetically identical diploid daughter cells.

Cytokinesis

The physical division of the cell cytoplasm into two individual cells following mitosis.

G0 Phase

A resting state of the cell cycle where mature cells, such as neurons or heart cells, permanently remain without dividing.

Prophase

The first phase of mitosis where chromatin condenses into chromosomes and centrioles migrate to opposite sides.

Metaphase

The stage of mitosis where chromosomes align neatly along the center equator of the cell.

Anaphase

The stage of mitosis where spindle fibers pull sister chromatids apart to opposite ends of the cell.

Telophase

The stage of mitosis where chromosomes decondense, nuclear membranes rebuild, and a cleavage furrow forms.

Meiosis

Specialized cell division of gametes involving two nuclear divisions that yields four genetically distinct haploid cells.

Synopsis

The close pairing of maternal and paternal homologous chromosomes during meiosis I.

Crossing Over

Also called genetic recombination; the exchange of DNA portions between paired homologous chromosomes during meiosis I, creating genetic variation.

Apoptosis

Programmed, gene-regulated cell death designed to safely destroy excess, damaged, or defective cells.

Benign Tumor

A non-invasive, localized mass of abnormally proliferating cells that does not metastasize.

Malignant Tumor

A cancerous mass of cells that invades surrounding tissue and can break off to metastasize throughout the body.