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Which one of the following lists shows the correct order of biological organization? - ✔✔Population, community, ecosystem, biosphere A modification that makes organisms more suited to their environment is called a/an: - ✔✔Adaptation During a scientific experiment, the control group is: - ✔✔Identical to the experimental group in all areas except the variable being tested When an atom has 2 or more electron shells, the outer shell will be most stable if it contains 8 electrons. This concept is called the: - ✔✔Octet rule When 2 oxygen atoms join together, a __ is formed. - ✔✔Molecule The __ bond is a type of atomic bonds in which atoms share electrons to produce a completed outer shell. - ✔✔Covalent The polarity of water molecules causes them to be attracted to one another by a __ bond. - ✔✔Hydrogen As the number of hydrogen ions in a solution increases, the pH of the solution: - ✔✔Decreases During winter only the upper surface of a lake freezes, which allows for life to persist below the surface. Which of water's unique properties is responsible for this phenomenon? - ✔✔Lower density as ice The most abundant element by weight in the human body is - ✔✔Oxygen
The polysaccharide structural carbohydrate most commonly used by living things is: - ✔✔Cellulose Which one of the following functional groups is associated with fatty acids? - ✔✔Carboxyl The hard body parts of insects and crabs are composed of a polysaccharide called: - ✔✔Chitin Cell membranes are composed mainly of which type of lipids? - ✔✔Phospholipids ___ proteins are made of polypeptide chains folded into rounded compact shapes. - ✔✔Globular When joined by a dehydration reaction, the covalent bond between the carboxyl groups of two amino acids is called a ____ bond. - ✔✔Peptide The sugar in RNA is: - ✔✔Ribose Within cells, the synthesis of proteins occurs in the: - ✔✔Ribosomes What is the main function of the mitochondria? - ✔✔Producing ATP The ___ keep(s) the cytoplasm of eukaryotic cells separate from the DNA. - ✔✔Nuclear envelope Organelles that use solar energy to make carbohydrates are called: - ✔✔Chloroplasts The ___ are sometimes called the "powerhouses" of the cell. - ✔✔Mitochondria The cell-to-cell junctions that allow cells to communicate are called ___ junctions. - ✔✔Gap In a/an ___ reaction, one reaction releases energy and the second uses energy. - ✔✔Coupled
What process results in 2 ATP and a toxic end product? - ✔✔Fermentation Besides carbon dioxide, the other end product of cellular respiration is: - ✔✔Water In cellular respiration, the number of ATP molecules produced equals about 40% of the energy available from a glucose molecule. The remainder of the energy is lost as: - ✔✔Heat Eukaryotic cells generally rely on a cytoskeletal generally rely on a cytoskeletal structure called a/an ___ to pull chromatids apart. - ✔✔Spindle A tumor that has invaded surrounding tissues is considered to be: - ✔✔Malignant In the cell cycle, DNA replication occurs during the ___ interval of interphase. - ✔✔S Which of the following lists the correct order of the stages of mitosis? - ✔✔Prophase, Metaphase, Anaphase, Telophase During which stage of mitosis does the nuclear envelope start to break down? - ✔✔Prophase During ___, the two copies of each chromosome separate from each other and begin to move to opposite poles. - ✔✔Anaphase The process by which cancer cells travel through the lymph or blood and start tumors in new locations of the body is called: - ✔✔Metastasis A ___ is a repeating DNA sequence found on the ends of chromosomes that acts as a "cap" that encourages chromosomal stability. - ✔✔Telomere How many chromosomes are located in a single human somatic cell? - ✔✔ 46
___ occurs in cells especially set aside for reproduction, but not in somatic cells. - ✔✔Meiosis In meiosis, the exchange of genetic material between nonsister chromatids occurs during: - ✔✔Prophase 1 The first cell that's formed when 2 gametes come together at fertilization is the: - ✔✔Zygote How many daughter cells result when a cell undergoes the process of meiosis? - ✔✔Four How many chromosomes are located in a single human gamete cell? - ✔✔ 23 Which of the following processes occurs during meiosis but not mitosis? A. Cytokinesis B. Telophase C. Cytogenesis D. Crossing-Over - ✔✔Crossing-over If an individual's alleles for a certain trait aren't identical, the individual is said to be: - ✔✔Heterozygous Assume that the allele for curly hair dominates the allele for straight hair. If a homozygous man with straight hair marries a homozygous curly-haired woman, we would expect their children to display which phenotypes? - ✔✔All would have curly hair What outcome would you expect if you cross a homozygous red tulip with a homozygous yellow tulip if red is incompletely dominant over yellow? - ✔✔All of the offspring will be orange The ability of primroses with the same genotype to express different phenotypes for flower color is an example of: - ✔✔An environmental effect on gene expression
In eukaryotes transcription ___ are DNA-binding proteins that assist RNA polymerase to bind to a promoter. - ✔✔Factors In general, a cell-signaling pathway begins when: - ✔✔A chemical signal binds to a receptor protein. ___ cloning refers to producing cells that might be used to repair spinal tissue injuries. - ✔✔Therapeutic ___ act as a carrier for foreign DNA. - ✔✔Vectors The first step of the ___ process denatures DNA at 95C to separate the strands. - ✔✔Polymerase chain reaction ___ is crucial to the development of new drugs. - ✔✔Proteomics 94% of ___ in the United States are genetically engineered. - ✔✔Soybeans The gene for ___ has been used to create larger fish and rabbits. - ✔✔Bovine growth hormone A ___ can be used to test DNA samples for known disease-causing mutated alleles. - ✔✔DNA microarray Chorionic villi sampling (CVS) involves drawing tissue samples from the region where the ___ will develop. - ✔✔Placenta ___ is the process of transferring normal or modified genes into an individual in an attempt to correct some type of genetic defect. - ✔✔Gene therapy A karyotype of a fetus finds that there are three number 21 chromosomes. This child will be afflicted with: - ✔✔Down syndrome
Williams syndrome results when a/an ___ occurs in chromosome 7. - ✔✔Deletion If a codon triplet makes no sense in respect to any protein used by the organism; it's most likely caused by a ___ mutation. - ✔✔Frameshift Which of the following factors is required for natural selection to occur? - ✔✔Organisms compete for limited resources How can you tell a population is evolving? - ✔✔Over generations, a larger portion exhibits favorable adaptations. Humans have a tailbone but no tail. This is a/an ___ structure. - ✔✔Vestigial From the Darwinian point of view, when humans breed cattle for certain traits, they're engaged in ___ selection. - ✔✔Artificial As a result of reading Thomas Malthus on the topic of human population increase, Darwin came up with the concept of: - ✔✔Survival of the fittest Evidence suggests that life's diversity has come about as the result of very slight differences in certain genes. This sort of observation is most likely to have arisen through examining ___ evidence. - ✔✔Molecular What mechanism creates new alleles? - ✔✔Mutation If we observe small changes in the frequency of an allele's appearance in a population's offspring due to mutation, natural selection, and genetic drift, we're observing: - ✔✔Microevolution Gene flow is the movement of alleles into and out of a population as a result of: - ✔✔Migration A group of individuals of the same species occupying a given area is a: - ✔✔Population
