Anatomy of a Representative Cell - Page 1-2 (Question and Answer Flashcards)

Question-and-answer flashcards covering plasma membrane, cytosol, nonmembranous organelles, and membranous organelles as described in the notes.

What is the composition of the plasma membrane (plasmalemma)?

Lipid bilayer containing phospholipids, steroids, proteins, and carbohydrates.

What does ECF stand for and what is it?

Extracellular fluid outside the cell.

What does ICF stand for in this context and where is it located?

Intracellular fluid; fluid inside cells.

What is the fluid component of the cytoplasm that may contain inclusions?

Cytosol.

What is the primary function of the plasma membrane?

Isolation, protection, sensitivity; control of entrance/exit of materials.

What is the role of cytosol in the cell?

Distributes materials by diffusion; stores glycogen, pigments, and other materials.

What is the cytoskeleton and its main function?

Proteins organized in fine filaments or slender tubes; provides strength and support; enables movement of cellular structures and materials.

What is a microtubule and its key functions?

A hollow filament of the cytoskeleton; essential for movement of chromosomes during cell division and organization of microtubules.

What is a microfilament and its role?

Actin filament; part of the cytoskeleton; involved in cell movement and shape.

What are microvilli and their function?

Membrane extensions containing microfilaments; increase surface area to facilitate absorption.

What is the centrosome and what does it contain?

Region near the nucleus containing two centrioles that organize microtubules.

What are centrioles and their purpose?

Cylindrical structures with nine microtubule triplets; part of the centrosome; organize the spindle apparatus during cell division.

What are cilia and what do they do?

Membrane extensions containing microtubule doublets in a 9+2 array; move materials across the cell surface.

What are ribosomes and where are they located?

RNA + proteins; may be fixed on rough ER or free in the cytoplasm; site of protein synthesis.

What is the mitochondrion and its primary energy function?

Double-membrane organelle with cristae; produces about 95% of the cell's ATP.

What is the nucleus and what are its main roles?

Double-mounded organelle containing DNA; controls metabolism, stores and processes genetic information, and controls protein synthesis.

What is the nuclear envelope?

Double membrane surrounding the nucleus with nuclear pores.

What is the nucleolus and its function?

Dense region in the nucleoplasm where DNA and RNA concentrate; site of rRNA synthesis and ribosomal subunit assembly.

What are nuclear pores?

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

What is nucleoplasm?

Fluid within the nucleus containing nucleotides, enzymes, nucleoproteins, and chromatin.

What is the endoplasmic reticulum (ER)?

Network of membranous channels; synthesizes and transports proteins and lipids.

What distinguishes rough ER from smooth ER?

Rough ER has ribosomes on its membranes and synthesizes/ processes proteins; Smooth ER lacks ribosomes and synthesizes lipids, steroids, carbohydrates, and stores calcium.

What is the Golgi apparatus and its function?

Stacks of flattened membranes that modify, package, and ship secretory products and lysosomal enzymes.

What is a lysosome?

Vesicles containing digestive enzymes; intracellular digestion and removal of damaged organelles or pathogens.

What is a peroxisome?

Vesicles containing enzymes for lipid metabolism and detoxification; breakdown of fats and neutralization of toxins.