BSC 1005 Exam #2 Examples Questions And Answers Solved

DNA has the capacity to - Correct Answers store genetic information, copy it, and pass it from one generation to the other generation. Chromatin is - Correct Answers DNA and proteins Nucleic acids - Correct Answers DNA and RNA; consist of long chains of nucleotides. Therefore nucleotides are monomers and nucleic acids are polymers. DNA is double stranded while - Correct Answers RNA is single stranded. Each nucleotide consists of 3 main parts; - Correct Answers a nitrogenous base with a purine or pyrimidine, a pentose sugar with 5 carbon atoms, and a phosphate group consisting of 1, 2, or 3 phosphate groups attached to the carbon atom. Purines - Correct Answers Adenine and Guanine Pyrimidines - Correct Answers Cytosine and Thymine Purines and Pyrimidines are connected by - Correct Answers a hydrogen bond. Adenine is to _ as Cytosine is to _. - Correct Answers Thymine; Guanine In RNA, Thymine is replaced by - Correct AnswersUracil. It is the order of these bases in a nucleic acid - Correct Answersthat specifies genetic information. Small hydroxyl groups hang from - Correct Answersthe sugar portion of the nucleotide. DNAs have one less - Correct AnswersO (H & OH), hence the name Deoxy ribose, than RNA. RNA has two - Correct AnswersOH groups. In cells, each DNA molecule is organized as - Correct Answersa chromosome. A chromosome - Correct Answersconsists of DNA and adssociated proteins, carries a cell' s genetic info. Genome (chromatin) - Correct Answersentire DNA center of the cell. Rungs of DNA are made of - Correct Answersnitrogen bases connected by hydrogen bonds. James Watson and Francis Crick - Correct Answerswon the Nobel prize for their 3D double helix model of DNA molecule. DNA contains - Correct Answersanti-parallel strands; oriented but in different directions. Hydrogen bond sticks strands together and - Correct Answersbreaks when replicating. Role of enzymes: - Correct AnswersDNA polymerase adds new nucleotides to new strand. To proofread pairs are correctly matched uses ATP. DNA ligase - Correct Answersparticipates in DNA repairs, fills in tiny gaps. Reproductive cloning - Correct AnswersResults in an exact genetic copy of an adult individual. Therapeutic cloning - Correct AnswersCloned human embryos used in making stem cells that are used in research. Human genome project - Correct AnswersThe determination of the complete nucleotide sequence of DNA of each human chromosome. Cell reproduction - Correct Answersliving cells dividing. Diploid cell - Correct Answersmade up of two sets of 23 chromosomes each. Haploid cell - Correct Answershas only one set of 23 chromosomes. Mitosis - Correct Answersa nuclear division mechanism that maintains the chromosome number. Consists of Prophase, Metaphase, Anaphase, and Telophase. Interphase - Correct AnswersThe cell preparing for cell division. Consists of G1, S, and G2. G1 - Correct Answers"Gap 1:" cell growth before DNA replication S - Correct Answers"Synthesis:" DNA replication G2 - Correct Answers"Gap 2:" preparation for division Cytokinesis - Correct Answersdivision of cytoplasm Prophase - Correct AnswersFirst; chromatin threads to chromosomes, nucleolus disappears, nuclear envelope breaks down, microtubules assemble. Chromosome structure - Correct Answerstwo sister chromatids make up one chromosome, sister chromatids are connected at the centromere region. Metaphase - Correct AnswersMiddle; Formation of spindle apparatus, chromosome move to equatorial plane, all 46 chromosomes are connected by spindle fibers. Anaphase - Correct AnswersAway; Separation of chromatids at the centromere region, daughter chromosomes (formerly sister chromatids) move to opposite poles Telophase - Correct AnswersEnd; reverse of prophase, new nuclear envelopes are formed, spindle fibers disappear, chromosomes to chromatin Cytokinesis process - Correct Answersconstriction of the plasma membrane in animals, formation of cell plate in plants, vesicles across the plane and gradually fuse to form a cell plate. Multi-celled organisms - Correct Answersgrow, repair dead or damaged cells and tissues by mitosis. A fertilized egg (zygote) - Correct Answersundergoes mitosis to accomplish growth. Mitosis results in two - Correct Answersidentical daughter cells with no change in chromosome number or genetic information. Growth factors are - Correct Answersmolecules that stimulate cells to divide and differentiate. An oncogene is - Correct Answersany gene that transforms a normal cell into a tumor cell. Neoplasms - Correct Answersan accumulation of abnormally dividing cells. Tumors and moles - Correct Answersabnormal masses of cells Benign tumor - Correct Answersnoncancerous neoplasms Cancers are - Correct Answersabnormally growing and dividing cells of a malignant neoplasm Malignant tumors - Correct Answerscan invade other tissues and may kill the organism. HeLa cells - Correct Answersfrom Henrietta Lacks, human cells grown in laboratories (most die within a few weeks) Three types of skin cancers - Correct Answersbasal cell carcinoma, squamous cell carcinoma, melanoma Basal cell carcinoma - Correct Answersthe most common type of skin cancer; slow growing Squamous cell carcinoma - Correct Answersthe second most common type of skin cancer Melanoma - Correct Answersspreads the fastest. Cancer causes - Correct Answers15%to 20% of all human deaths. Asexual reproduction - Correct Answersproduces genetically identical copies of the parent. Sexual reproduction - Correct Answersinvolves the formation of sex cells (gametes) to make zygotes Somatic cells - Correct Answersdo not play a role in reproduction. They are diploid. Germ cells - Correct Answersare set aside for the function of reproduction. Homologous pairs - Correct Answersthe two chromosomes that make up a matched pair in a diploid cell of an organism. One is inherited from the father, the other from the mother. Homologous chromosomes are of the same - Correct Answerslength, centromere, position, and possess the same genes or alternative form of the gene.