A&P Chapter 3 Flashcards

Structure and Function of Cells

• Cells consist of three main parts: Plasma membrane, Cytoplasm, and Nucleus.
• Plasma membrane components include membrane lipids, membrane proteins, and carbohydrates.
• Functions as a selective barrier, allowing certain substances to pass through while blocking others.

Membrane Permeability

• Large polar molecules and charged substances cannot pass through the plasma membrane.
• Small gases, non-polar substances, and small polar molecules like water can freely pass through.

Tonicity and Solutions

• Tonicity measures a solution's ability to affect cell volume by altering water concentration.
• Isotonic solutions maintain cell size and shape due to equal concentrations of solutes and water.
• Hypertonic solutions cause cells to lose water and shrink, having higher solute concentrations outside.
• Hypotonic solutions make cells swell and potentially burst, containing lower solute concentrations than inside cells.

Organelles and Their Functions

• Organelles are specialized compartments within cells that perform distinct functions.
• Mitochondria are known as the powerhouse of the cell, where ATP synthesis occurs.
• Ribosomes are the sites of protein synthesis.
• Rough Endoplasmic Reticulum (Rough ER) modifies and transports proteins; it is studded with ribosomes.
• Smooth Endoplasmic Reticulum (Smooth ER) is involved in lipid synthesis and detoxification processes.

Golgi Apparatus and Lysosomes

• The Golgi apparatus sorts and processes proteins, consisting of stacked smooth sacs and vesicles.
• Lysosomes digest intracellular debris, acting as the cell's garbage disposal.

Cytoskeletal Structures

• Cytoskeletal organelles include microfilaments (actin strands), intermediate filaments (tough protein fibers), and microtubules (hollow tubes of tubulin) which provide structural support.

Cellular Extensions

• Cellular extensions enhance motility or increase surface area; examples include cilia, flagella, and microvilli.
• Cilia are short and create a unidirectional current for moving substances across surfaces.
• Flagella are longer and propel cells, such as sperm cells.
• Microvilli increase surface area, aiding in absorption.

Nucleus

• The nucleus is the control center of the cell, with a structure including the nuclear envelope, chromatin, and nucleolus.
• The nuclear envelope separates nucleoplasm from cytoplasm and regulates substance passage.

Cell Cycle and Mitosis

• Mitosis is the nuclear division process that results in two daughter nuclei.
• Interphase is the cell's phase of normal activity and growth.
• Prophase involves chromatin condensation into chromosomes; late prophase sees nuclear envelope fragmentation.
• Metaphase aligns chromosomes at the cell's equator, with centrosomes at opposite poles.
• Anaphase marks the separation of chromatids, becoming individual chromosomes.
• Telophase begins when chromosomal movement stops, followed by cytokinesis which divides the cytoplasm into two identical daughter cells.

RNA Types and Genetic Processes

• Messenger RNA (mRNA) serves as a copy of DNA for protein synthesis.
• Ribosomal RNA (rRNA) is a component of ribosomes.
• Transfer RNA (tRNA) transports amino acids to ribosomes during protein synthesis.
• Transcription is the process where DNA is transcribed to mRNA, tRNA, and rRNA.
• Diploid cells contain a full set of chromosomes (46 total).
• Haploid cells have one chromosome from each pair.
• Human somatic cells have 46 chromosomes or 23 pairs.
• The Central Dogma of molecular biology describes the flow of genetic information: DNA → RNA → Protein.

Protein Synthesis

• Translation is the process of converting mRNA's nucleotide language into amino acid sequences for protein formation.

Test your knowledge of the essential components and functions of cells with these flashcards from Anatomy & Physiology Chapter 3. Covering everything from the structure of the plasma membrane to its selective permeability, these cards are perfect for mastering cell biology concepts.