Anatomy & Physiology I: Cytology and Cell Growth

This set of flashcards covers key terms and concepts related to the Anatomy & Physiology I lecture on Cytology and the Cell Cycle.

Cytoplasm

The entire cellular material surrounding the nucleus, enclosed by the plasma membrane, composed of cytosol, organelles, cellular structures, and cellular inclusions.

Organelles

Specialized structures within a cell that perform distinct processes; examples include mitochondria and Golgi apparatus.

Mitochondrion

An organelle that is the site for ATP synthesis, characterized by a double membrane and a matrix.

Endoplasmic Reticulum (ER)

A system of membranous channels and cisterns continuous with the outer membrane of the nuclear envelope, involved in protein and lipid synthesis.

Golgi Apparatus

Stacked and flattened membranous sacs that process, package, and distribute molecules.

Peroxisomes

Small, spherical, single-membranous sacs containing oxidative enzymes that detoxify substances and break down fatty acids.

Lysosomes

Small, spherical, single-membranous sacs containing digestive enzymes, abundant in phagocytes, and require an acidic environment.

Ribosomes

Machinery for protein synthesis composed of two subunits of rRNA and riboproteins; can exist freely or be membrane-bound.

Cytoskeleton

A network of macromolecular fibers maintaining cell shape and assisting in movement, consisting of microfilaments, intermediate filaments, and microtubules.

Centrosomes

Microtubule-organizing regions near the nucleus involving cell division and containing centrioles.

Cilia

Short, hairlike extensions on cell surfaces that move together in a sweeping motion.

Flagella

Long extensions on cell surfaces that propel the whole cell.

Microvilli

Minute, fingerlike extensions from the plasma membrane that increase surface area for absorption.

Cell Cycle

An ordered sequence of events involving cell growth and nuclear division, consisting of interphase and mitosis.

Interphase

The stage of the cell cycle where cellular growth and DNA synthesis occurs, comprising G1, S, and G2 stages.

Mitosis

The stage of the cell cycle in which nuclear division occurs, consisting of prophase, metaphase, anaphase, telophase, and cytokinesis.

Transcription

The process of synthesizing RNA from a DNA template, essential for gene expression.

Translation

The process through which the sequence of nucleotides in mRNA directs the addition of amino acids to form a polypeptide chain.

Genetic Code

Instructions within a gene that determine which protein is made; consists of 64 codons that code for amino acids and stop signals.

Aminoacyl-tRNA Synthetases

Enzymes that couple specific amino acids to their corresponding tRNA during protein synthesis.

Pre-mRNA Processing

The modifications made to pre-mRNA before it exits the nucleus, including capping, polyadenylation, and splicing.

Plasma Membrane

The lipid bilayer that surrounds and protects the cell, regulating what enters and exits the cell.

Nucleus

The organelle that houses the cell's genetic material (DNA) and is responsible for regulating cellular activities.

Chromosomes

Tightly coiled structures made of DNA and proteins; they carry genetic information.

Gene

A segment of DNA that contains the instructions for making a particular protein.

Cellular Respiration

The process by which cells convert glucose and oxygen into energy (ATP), carbon dioxide, and water.

Apoptosis

Programmed cell death that occurs as a normal part of development and health.

Cell Differentiation

The process by which unspecialized cells develop into their mature forms and functions.

Stem Cells

Undifferentiated cells that have the potential to develop into any type of cell in the body.

Biogenesis

The principle that living organisms arise only from other living organisms.

Endocytosis

The process by which cells take in substances by engulfing them in a vesicle.

Cell Membrane

A semipermeable barrier that surrounds the cell, composed of a lipid bilayer and proteins, regulating the movement of substances in and out of the cell.

Nucleolus

A dense structure within the nucleus responsible for the production of ribosomal RNA (rRNA) and assembly of ribosome subunits.

Vesicles

Small, membrane-bound sacs that transport substances within a cell or to the cell membrane for export.

Phagocytosis

A type of endocytosis in which the cell engulfs large particles or cells, often used by immune cells to remove pathogens.

Exocytosis

The process by which substances are expelled from the cell through vesicles that fuse with the plasma membrane.