Anatomy and Physiology Chapter 3 Practice Test

What are the building blocks of all plants and animals - answer-cells All of the following are membranous organelles EXCEPT - answer-microvilli and centrioles Most of the surface area of the plasma membrane consists of - answer-phospholipids Because of the chemical-structural composition, the plasma membrane is called a - answer-phospholipid bilayer The cytoskeleton gives the cell strength and rigidity and anchors the position of major organelles. What are the primary components of the cytoskeleton - answer-microtubules Most of the energy a cell needs to live is generated by the - answer-mitochondria Which organelle absorbs and breaks down fatty acids and other organic compounds - answer-peroxisome Ribosomal proteins and RNA are produced primarily in the - answer-nucleolus Along the length of the DNA strand, information is stored in the sequence of - answer-nitrogenous bases A sequence of three nitrogen bases can specify the identity of - answer-a single amino acid What is the process in which RNA polymerase uses the genetic information to assemble a strand of mRNA - answer-transcription If the DNA triplet is TAG, the corresponding codon on the mRNA strand will be - answer-AUG Protein channels within the plasma membrane - answer-permit water and ion movement at all times Ions and other small, water-soluble materials cross the plasma membrane only by passing through - answer-a channel All transport through the plasma membrane can be classified as either - answer-active or passive A sequence of three nucleotide bases in the mRNA is called a - answer-codon What is the functional unit of heredity - answer-gene Which of the following is an important characteristic of the transmembrane potential - answer-the ions held on either side of the plasma membrane have potential energy Which of the following is true of transmembrane potential - answer-all of the listed responses are correct In which phase does a cell make enough organelles for two functional cells - answer-G1 In which phase does the centriole replication complete - answer-G2 The four stages of mitosis in correct sequence are - answer-prophase, metaphase, anaphase, telophase As the cell life cycle proceeds, cyclin levels climb, causing the maturation promoting factor (MPF) to appear in the cytoplasm, initiating the process of - answer-mitosis The spreading process of a primary tumor is called _____, and the dispersion of a malignant cells to establish a secondary tumor is called ____ - answer-invasion; metastasis The process of differentiation resulting in the appearance of characteristic cell specializations involves - answer-gene repression (switching off) In which phase of mitosis do the chromosomes align in the center of the cell - answer-metaphase Structurally, the plasma membrane is best described as - answer-phospholipid bilayer interspersed with proteins The cell membrane isolates the cytoplasm from the surrounding fluid environment. Why is this important - answer-Cytoplasm has a composition different from that of the extracellular fluid, and the differences must be maintained Which type of vesicular transport used pseudopodia to surround a solid object - answer-phagocytosis Membranous organelles differ from non-membranous organelles in that membranous organelles are - answer-surrounded by lipid membranes that isolate them from the cytosol Cilia function to - answer-move fluids or secretions across the cell surface The smooth endoplasmic reticulum (SER) has a variety of functions that center around the synthesis of - answer-lipids and carbohydrates Why are lysosomes sometimes called "cellular suicide packets" - answer-the breakdown of lysosomal membranes can destroy a cell The energy-producing process in the mitochondria involves a series of reactions in which ____ is consumes and ____ is generated - answer-oxygen; carbon dioxide What is the most notable characteristic of the G0 phase of an interphase cell - answer-the cell is not preparing for mitosis The replication of DNA occurs primarily during which phase - answer-S phase The process of cytokinesis refers to - answer-the physical separation of the daughter cells The genetically controlled death of cells is called - answer-apoptosis Which of the following factors influence diffusion rates - answer-distance, temperature, and molecular size Water-soluble ions and molecules CANNOT enter certain regions of the cell membrane because of - answer-the presence of hydrophobic tails on the interior of the membrane The effect of diffusion in body fluids is that it tends to - answer-eliminate local concentration gradients During osmosis, water will always flow across a membrane toward the solution that has - answer-the higher concentration of solutes A solution that is hypotonic to the cytoplasm has a - answer-a solute concentration lower than that of the cytoplasm Red blood cells are hemolyzed when the cells are placed in contact with - answer-a hypotonic solution An injection of a concentrated salt solution into the circulatory system would result in - answer-crenation of the red blood cells How does facilitated diffusion differ from ordinary diffusion - answer-carrier proteins are involved Which of the following is one of the great advantages of moving materials by active transport - answer-the process is not depended on a concentration gradient Which of the following is an example of the process of phagocytosis in the human body - answer-a white blood cell engulfing a bacterium The difference between an area of high concentration of solute and an area of low concentration of solute is known as - answer-a concentration gradient What does the formation of a malignant tumor indicate - answer-mitotic rates