A/P Lab Quiz 2

Comprehensive vocabulary flashcards detailing organelle structures, functions, cellular extensions, and stages of cell division based on lecture notes.

A transparent barrier that encloses cell contents, separates them from the outer environment, controls the passage of materials, maintains electrical conditions in excitable cells, and contains receptors for communication.

Plasma Membrane

The largest organelle and control center of the cell that contains DNA, responsible for transmitting genetic information and providing instructions for protein synthesis.

Nucleus

A double-membrane structure pierced by large pores that separates nucleoplasm from cytoplasm and regulates the movement of substances into and out of the nucleus.

Nuclear Envelope

A dense, spherical, non-membrane-bounded body located inside the nucleus composed of ribosomal RNA and proteins; serves as the site of ribosome subunit manufacture.

Nucleolus

Granular, threadlike material composed of DNA and histone proteins ('beads on a string') that carries genetic instructions and coils into chromosomes during cell division.

Chromatin

The cellular material outside the nucleus and inside the plasma membrane, serving as the site of most cellular activities; consists of fluid cytosol, organelles, and inclusions.

Cytoplasm

The fluid portion of the cytoplasm that contains dissolved solutes.

Cytosol

Rodlike, double-membrane structures with inner folds called cristae; known as the 'powerhouses' of the cell that use oxygen to break down food and synthesize ATP.

Mitochondria

Dense particles composed of two subunits of ribosomal RNA and protein, located free in the cytoplasm or attached to rough ER, which serve as the sites of protein synthesis.

Ribosomes

A membranous system enclosing cavities and studded externally with ribosomes; synthesizes proteins, attaches sugar groups to proteins, and packages them in transport vesicles.

Rough Endoplasmic Reticulum (RER)

A membranous system of tunnels and sacs free of ribosomes that functions in lipid and steroid (cholesterol) synthesis, lipid metabolism, and drug detoxification.

Smooth Endoplasmic Reticulum (SER)

A stack of flattened membranes and associated vesicles that modifies, packages, and segregates proteins arriving from the rough ER via transport vesicles.

Golgi Apparatus

Membranous sacs containing acid hydrolases (powerful digestive enzymes) that perform intracellular digestion of nonusable structures, cell debris, and bacteria; known as the 'stomach' of the cell.

Lysosomes

Membranous sacs containing oxidase and catalase enzymes that detoxify harmful substances (such as alcohol and free radicals) by converting them to hydrogen peroxide and then water.

Peroxisomes

The primary enzyme in peroxisomes responsible for breaking down hydrogen peroxide into harmless water and oxygen.

Catalase

An internal network of protein structures extending throughout the cytoplasm (microfilaments, intermediate filaments, microtubules) that determines cell shape, supports organelles, and enables transport.

Cytoskeleton

Cylindrical cytoskeletal elements made of tubulin proteins that support cell shape, participate in intracellular movement, and form centrioles, cilia, and flagella.

Microtubules

Fine cytoskeletal filaments composed of actin protein involved in cell motility, muscle contraction, and forming microvilli and the cleavage furrow.

Microfilaments

Stable cytoskeletal protein fibers of varying composition that resist mechanical forces acting on the cell.

Intermediate Filaments

Paired cylindrical bodies, each composed of $9$ triplets of microtubules, that organize the mitotic spindle during cell division and form the bases of cilia and flagella.

Centrioles

Cellular surface extensions that move substances across the cell surface, such as moving mucus in the human respiratory system.

Cilia

Long surface extensions that propel the entire cell; sperm is the only flagellated cell type in the human body.

Flagella

Tiny, fingerlike extensions of the plasma membrane that increase cell surface area for absorption.

Microvilli

Chemical substances stored in the cytoplasm, such as lipid droplets, glycogen granules, protein crystals, and pigment granules.

Inclusions

The metabolic phase of the cell cycle where the cell grows, conducts normal functions, and replicates its DNA prior to division.

Interphase

The division of the cell nucleus, consisting of prophase, metaphase, anaphase, and telophase, resulting in two identical daughter nuclei.

Mitosis

The division of the cytoplasm that begins in late anaphase and completes during telophase, producing two distinct daughter cells.

Cytokinesis

The first stage of mitosis during which chromatin coils into sister chromatids joined by a centromere, centrioles assemble the mitotic spindle, and the nuclear envelope breaks down.

Prophase

The stage of mitosis where chromosomes align in a straight line in the center of the cell along the metaphase plate.

Metaphase

The stage of mitosis where centromeres split and sister chromatids separate into daughter chromosomes, moving slowly toward opposite ends of the cell.

Anaphase

The final stage of mitosis where chromosomes uncoil back into chromatin, spindles disappear, nuclear envelopes re-form, and nucleoli reappear in each daughter nucleus.

Telophase

A contractile ring of microfilaments that forms to pinch the cell cytoplasm into two separate parts during cytokinesis.

Cleavage Furrow