AP Chapter 3: Cell Structure and Function

Flashcards covering AP Chapter 3 lecture notes regarding cell organelles, functions, transport, division phases, and cellular disorders.

Cell

The basic unit of structure and function.

Cell or plasma membrane

A double phospholipid layer with protein that separates the cell from the external environment and neighboring cells; it acts as a selective semipermeable membrane.

Nucleus

The most important organelle in the cell which functions in contractivity and facilitates division.

Chromosomes

Rod-like structures made of DNA and protein that contain genetic information; humans have $46$ chromosomes or $23$ pairs.

Nuclear membrane (Nuclear Envelope)

A double-layered permeable membrane with pores that regulates the transport of substances in and out of the nucleus.

Nucleoplasm

A clear, semi-liquid that fills the spaces around the chromatin and nucleoli.

Nucleolus

A ribosome reservoir; a cell may contain one or more nucleoli.

Ribosomes

Composed of RNA (Ribonucleic Acid) and protein, they pass freely from the nucleus into the cytoplasm and serve as the site for protein synthesis.

Cytoplasm

An organized, watery environment that provides the background for all chemical reactions; contains proteins, lipids, carbohydrates, minerals, salts, and water.

Centrosome

Located close to the nucleus, it contains two centrioles that separate during mitosis to produce the spindle fiber apparatus.

Endoplasmic reticulum

A passage for the transport of substances in the cytoplasm and a storage area for protein.

Rough Endoplasmic reticulum

Contains ribosomes and is used for protein synthesis.

Smooth Endoplasmic reticulum

Site for cholesterol synthesis, fat metabolism, and the detoxification of drugs.

Mitochondria

The powerhouse of the cell; the site of cellular respiration and energy production where ATP (adenosine triphosphate) is stored.

Golgi body apparatus

Manufactures carbohydrates and packages secretions for discharge from the cell, such as in gastric, salivary, and pancreatic glands.

Lysosomes

Known as suicide bags, they perform cellular digestion of proteins, old worn-out cells, bacteria, and foreign matter.

Peroxisomes

Organelles containing enzymes that oxidize cell substances, digest fats, and detoxify harmful substances.

Cytoskeleton

The internal framework of the cell consisting of microtubules for movement and intermediate filaments and microfilaments for support.

Pinocytic Vesicles

Mechanism allowing large molecules like proteins and lipids to enter the cell by forming a bubble or vacuole pocket in the cell membrane.

Cilia and flagella

External hairlike protrusions that create movement, moving material across the cell surface or propelling the cell.

Cellular metabolism

Chemical reactions that maintain structure and function in the cell, producing energy (ATP) from the decomposition of organic molecules.

Meiosis

Cell division for reproduction that reduces the number of chromosomes in sex cells (gametes) from $46$ to $23$.

Mitosis

Cell division for growth and maintenance consisting of nucleus division and cytoplasm division.

Phase I: Interphase

The resting stage of mitosis where replication or DNA duplication occurs to form chromatids.

Phase II: Prophase

Mitosis phase where centrioles migrate to opposite ends, the spindle fiber apparatus forms, and the nuclear membrane dissolves.

Phase III: Metaphase

Mitosis phase where the nuclear membrane is completely dissolved and chromosomes arrange in a single file on the equatorial plate.

Phase IV: Anaphase

Mitosis phase where chromosome pairs separate and are pulled toward the centrioles.

Phase V: Telophase

Final mitosis phase where chromosomes finish migration, uncoil into chromatin granules, and the nuclear membrane and nucleus reappear.

Necrosis

Unprogrammed death of cells and living tissue caused by factors such as injury, infection, cancer, or toxins.

Apoptosis

Regulated process where cells intentionally die; the cell intakes, regulates, and executes its own death.

mRNA

Carries instructions from DNA to the ribosome for protein synthesis.

Diffusion

Passive transport where molecules (gas, liquid, or solid) spread themselves evenly through a medium, moving from a greatly concentrated area to a less concentrated area.

Osmosis

The diffusion of water or other solvent molecules through a selective permeable membrane; can involve isotonic, hypotonic, or hypertonic solutions.

Filtration

The movement of solutes and water across a semipermeable membrane from high pressure to low pressure using mechanical force like gravity or blood pressure.

Active transport

The movement of molecules across a membrane from higher concentration against a concentration gradient to lower concentration, requiring an energy source.

Phagocytosis

A process in which particles are engulfed and digested by the cell.

Pinocytosis

A process in which solutions are ingested for the cell's own use.

Atrophy

A decrease in cell size often caused by aging or disease.

Hypertrophy

An increase in cell size due to an increase in workload.

Hyperplasia

An increase in the number of cells due to hormone stimulation.

Metaplasia

The ability of a cell to change into another cell type.

Dysplasia

A change in cell size, shape, and organization, often considered a precancerous state.

Neoplasia

A change in cell structure characterized by uncontrolled growth.

Hypoxia

A condition defined by decreased oxygen.

Anoxia

A condition defined by no oxygen.

Benign tumor

A neoplasm confined to a local area and usually surgically removed.

Malignant tumor

Cancer; a growth that continues to expand, crowds out healthy cells, and interferes with body functions.

Metastasis

The spread of cancer (malignant cells) to other parts of the body.

In Situ

Cancer that remains in its original location.