Chapter 3: Cells – Key Concepts (Quiz Flashcards)

A set of Question-and-Answer flashcards covering cell structure, organelles, membrane transport, cell projections, and the cell life cycle based on the lecture notes.

What is the nucleus and its primary function?

The control center of the cell that contains genetic material.

Name the three regions of the nucleus.

Nuclear envelope, chromatin, and nucleolus.

What is chromatin made of?

DNA and protein.

What is the nucleolus?

Region where ribosomes are assembled.

What are nuclear pores?

Openings in the nuclear envelope that regulate transport between the nucleus and cytoplasm.

What is the plasma membrane and its basic structure?

A barrier for cell contents made of a double phospholipid bilayer with hydrophilic heads and hydrophobic tails.

What are microvilli and their function?

Finger-like projections that increase surface area for absorption.

What are tight junctions?

Impermeable junctions that bind cells into leakproof sheets.

What are desmosomes?

Anchoring junctions that prevent cells from being pulled apart.

What are gap junctions?

Permissive channels that allow communication between adjacent cells.

What are the three major components of the cytoplasm?

Cytosol, organelles, and inclusions.

What is rough endoplasmic reticulum (RER)?

Transports proteins manufactured by ribosomes.

What is smooth endoplasmic reticulum (SER)?

Involved in lipid synthesis, detoxification, and drug metabolism.

What is the Golgi apparatus?

Packages and ships proteins and lipids; the cell’s traffic director.

What is the mitochondrion?

Powerhouse of the cell; generates ATP for cellular activities.

What are ribosomes?

Organelle where proteins are synthesized (protein factories).

What are lysosomes?

Membranous sacs containing enzymes that digest worn-out or nonusable materials.

What are peroxisomes?

Contain enzymes that detoxify harmful substances; break down fatty acids.

What is the cytoskeleton and its components?

A network of protein filaments: microfilaments, intermediate filaments, and microtubules.

What are microfilaments?

Smallest cytoskeletal elements involved in cell movement and shape change.

What are intermediate filaments?

Filaments that resist pulling forces on the cell.

What are microtubules?

Hollow tubes that determine cell shape and move organelles; built from tubulin.

What are cilia and their function?

Hair-like projections that move materials across the cell surface; present in the respiratory tract.

What is the function of flagella in humans?

The only flagellated cell is the sperm, which uses a flagellum for locomotion.

What is diffusion?

Movement of particles from high to low concentration; passive transport.

What is osmosis?

Diffusion of water across a selectively permeable membrane.

What is facilitated diffusion?

Diffusion that requires a carrier protein for lipid-insoluble or large substances.

What is filtration?

Movement of solutes through a membrane driven by a pressure gradient.

What is selective permeability?

Plasma membrane allows some substances to pass while excluding others.

What is active transport?

Movement of substances against a concentration gradient that requires ATP; includes solute pumping and vesicular transport.

What is the sodium-potassium pump?

A common active transport pump that moves Na+ out and K+ in to maintain ionic gradients.

What is endocytosis?

Process of taking substances into the cell; includes phagocytosis and pinocytosis.

What is exocytosis?

Vesicular transport that ejects materials from the cell to the extracellular space.

What is phagocytosis?

Cell eating; engulfment of large solid particles like bacteria.

What is pinocytosis?

Cell drinking; uptake of small amounts of liquid with dissolved particles.

What are interphase and cell division?

Interphase: cell growth and DNA replication; Mitosis and cytokinesis: division to form two daughter cells.

What are the stages of mitosis?

Prophase, metaphase, anaphase, and telophase (followed by cytokinesis).

What is DNA replication?

Duplication of genetic material toward the end of interphase, producing two identical chromatids.

What are centrioles, spindle, and centromere?

Centrioles form the mitotic spindle; spindle moves chromosomes; centromere holds sister chromatids together.