BIO 210 - CHAPTER 3 EXAM | QUESTIONS & ANSWERS (VERIFIED) | LATEST UPDATE | GRADED A+

1 BIO 210 - CHAPTER 3 EXAM | QUESTIONS & ANSWERS (VERIFIED) | LATEST UPDATE | GRADED A+ Plasma membrane Correct Answer: forms the outer boundary of the cell Cellular organelles Correct Answer: each performs specific functions Nucleus Correct Answer: contains the cell's genetic material and directs cell activities Cytoplasm Correct Answer: the material between the plasma membrane and nucleus Main functions of cells Correct Answer: -cell metabolism and energy release -synthesis of molecules -communication -reproduction and inheritance 2 Plasma membrane Correct Answer: also called the plasmolemma or cell membrane Functions of the plasma membrane Correct Answer: -encloses and supports the cell contents -acts as a selective barrier that regulates what goes into and out of the cell -plays a role in communication between cells -separates intracellular substances from extracellular substances Intracellular Correct Answer: inside cells Extracellular (intercellular) Correct Answer: between cells also called interstitial fluid Lipid bilayer Correct Answer: double layer of phospholipids with imbedded proteins Membrane proteins Correct Answer: protein molecules that "float" among the phspholipid molecules; either embedded in or attached to the phospholipid bilayer 3 Attachment proteins Correct Answer: proteins that allow cells to attach to other cells Transport proteins Correct Answer: proteins that move ions and molecules across the membrane Receptor proteins Correct Answer: proteins that attach to chemical signals on the cell surface Enzymes Correct Answer: proteins that catalyze chemical reactions Membrane carbohydrates Correct Answer: carbs that act as a marker molecules on the cell surface and allow cells to identify "self" versus "non-self" Glycoproteins Correct Answer: proteins attached to carbohydrates on the cell surface Glycolipids Correct Answer: lipids attached to carbs on the cell surface Glycocalyx 4 Correct Answer: composed of glycolipids and glycoproteins; allows cells to recognize each other (cell-to-cell recognition) Chloesterol Correct Answer: embedded between phospholipid molecules; gives membrane strength and rigidity Selectively permeable Correct Answer: allows some substances but not all to pass through Diffusion Correct Answer: movement of molecules from an area of higher concentration to an area of lower concentration until equilibrium is reached Solution Correct Answer: any mixture of liquids, gases, or solids in which the substances are uniformly distributed Solute Correct Answer: anything that dissolves in the solution Solvent Correct Answer: the part of the solution that is responsible for dissolving the solute 5 Concentration gradient Correct Answer: the concentration difference of a substance across a membrane Osmosis Correct Answer: the diffusion of water across a selectively permeable membrane Aquaporins Correct Answer: channels in membranes for water to pass through; usually only used for large amounts of water Hypotonic solutions Correct Answer: solutions that have a higher water concentration and a lower solute concentration than another solution Hypertonic solutions Correct Answer: solutions have a lower water concentration and a higher solute concentration than another solution Hemolysis Correct Answer: the bursting of a red blood cell due to it being placed into a hypotonic solution 6 Crenation Correct Answer: the shriveling of a red blood cell when put in a hypertonic solution Isotonic Correct Answer: when the concentration of solutes are equal to that inside the cells Mediated transport Correct Answer: process by which transport proteins mediate, or assist in, the movement of ions and molecules across the plasma membrane Channel proteins Correct Answer: proteins that form membrane channels (ion channels) for specific ions to pass through ex: sodium channels, potassium channels Carrier proteins Correct Answer: bind to ions or molecules and transport them across the membrane Facilitated diffusion Correct Answer: movement of ions by a carrier protein, from higher concentration to lower concentration across the membrane ATP-powered pumps 7 Correct Answer: move ions or molecules against their concentration gradient using the energy from ATP Antiport Correct Answer: when two substances are moved in the opposite direction Symport Correct Answer: when two molecules are being pumped in the same direction Vesicular transport Correct Answer: transport of large particles and macromolecules across a plasma membrane Endocytosis Correct Answer: the movement of materials into cells by formation of a vescicle Phagocytosis Correct Answer: the movement of solid material into cells ex: white blood cells eating bacteria Pinocytosis Correct Answer: the uptake of small droplets of liquids 8 Receptor-mediated endocytosis Correct Answer: involves plasma membrane receptors attaching to molecules before they are taken into the cell ex: cholesterol Exocytosis Correct Answer: the secretion of materials from cells by vesicle formation Cytosol (intracellular fluid) Correct Answer: supports the cell and enables cell movements Microtubules Correct Answer: -provide support -aid in cell division -components of cilia and flagella Microfilaments (actin filaments) Correct Answer: -support the plasma membrane -define the shape of the cell Intermediate filaments Correct Answer: provide support to the cell 9 Cytoplasmic inclusions Correct Answer: aggregates of chemicals either produced by the cell or taken in by the cell Nuclear envelope Correct Answer: consists of two separate membranes with nuclear pores; encloses jellylike nucleoplasm Chromatin Correct Answer: loosely arranged strands of DNA not visible under the microscope Nucleolus Correct Answer: -produces ribosomal ribonucleic acid (rRNA) -site of synthesis of ribosomal subunits Ribosomes Correct Answer: site of protein synthesis Free ribosomes Correct Answer: ribosomes that are not attached to any organelles; synthesize proteins used inside the cell Attached ribosomes 10 Correct Answer: ribosomes that are part of a network of membranes called the rough endoplasmic reticulum and they produce proteins that are secreted from the cell Endoplasmic reticulum Correct Answer: series of membranes forming sacs and tubules that extend from the outer nuclear membrane into the cytoplasm Rough ER Correct Answer: -studded with ribosomes -major site of protein synthesis Smooth ER Correct Answer: -does not have ribosomes attached -major site of lipid and carbohydrate synthesis Golgi apparatus Correct Answer: series of closeley packed membranous sacs that collect, package, and distribute proteins and lipids produced by the ER Vesicles Correct Answer: small, membrane-bound sacs that transport material from the Golgi apparatus to the exterior of the cell 11 Lysosomes Correct Answer: -vesicles comboning digestive enzymes -digest ingested bacteria, viruses, and toxins -digest nonfunctional organelles -can destroy entire cell during programmed cell death Peroxisomes Correct Answer: -vesicles containing enzymes -breakdown fatty acids, amino acids, and hydrogen peroxide -detoxify harmful or toxic substances -neutralize dangerous free radicals Mitochondria Correct Answer: -the major site of ATP production -have a smooth outer membrane and an inner membrane that is folded into cristae Centrioles Correct Answer: cylindrical organelles located in the centrosomes Centrosome Correct Answer: a specialized zone of the cytoplasm; the site of microtubule formation Spindle fibers 12 Correct Answer: microtubles involved in cell division; produced by centrioles Cilia Correct Answer: hair-like projections that move substance across the surface of cells Flagella Correct Answer: tail-like projection that propel sperm cells Microvilli Correct Answer: finger-like folds in the plasma membrane of cells that increase the surface area and aid in absorption and secretion Mitosis Correct Answer: cell division that produces new cells for growth and tissue repair Meiosis Correct Answer: cell division that produces gametes Somatic cells Correct Answer: -body cells that are diploid -46 diploid number Gametes 13 Correct Answer: -cells that have a haploid number -23 haploid number Interphase Correct Answer: -the time between cell divisions -DNA is found as thin threads of chromatin in the nucleus -during this phase, the cell is preparing for cell division -organelles, other than the nucleus, duplicate during this phase -DNA replication occurs during this phase Prophase Correct Answer: -chromatin condenses and becomes visible -centrioles begin to move to the opposite ends -centrioles begin to produce spindles fibers -nucleolus and the nuclear envelope disappear Metaphase Correct Answer: -chromosomes align in the center of the ccell -spindle fibers are attached to the centromere of each chromosome Anaphase Correct Answer: -the chromatids separate and each chromatid is then referred to as a chromosome 14 -the chromosomes, assisted by the spindle fibers, move toward the centrioles at each end of the ccell Telophase Correct Answer: -migration of each set of chromosomes is complete -the chromosomes unravel to become chromatin threats -the nuclear envelope and nucleolus reform Cytokineses Correct Answer: splitting of the cytoplasm Cleavage furrow Correct Answer: indentation that forms between the two new cells during cytokinesis Differentation Correct Answer: process by which cells develop specialized structures and functions