BIOLOGY LECTURE

• Aneuploid


  A variation in chromosome number where an organism gains or loses one or more chromosomes but not a complete set.
• Polyploid


  A variation in chromosome number where an organism gains more than 2 sets of chromosomes but not a complete set.
• Trisomy


  Down syndrome is a genetic condition caused by an extra chromosome. What type of chromosomal abnormalities occur in this situation?
• Below are the advantages of polyploid,

  EXCEPT______.

  • Sterility
  • Hybrid vigor
  • Increase genetic diversity
  • Increase disease resistance
  • Enhanced adaptability
• Allopolyploid


  It refers to the combination of chromosome sets from different species occurring as a consequence of hybridization.
• Monosomy


  What is the term for the loss of one chromosome resulting in a 2n - 1 complement?
• Down Syndrome 


  What abnormalities or syndrome is expressed from this karyogram?

  
• Patau Syndrome 


  What abnormalities or syndrome is expressed from this karyogram?

  
• Identify the variation in chromosomal structure observed in figure A-D.

  Figure A: Deletion

  Figure B: Duplication

  Figure C: Paracentric Inversion

  Figure D: Reciprocal Translocation

  
• Identify the variation in chromosomal structure observed in this figure.

  Robertsonian Translocation

  
• Turner Syndrome 


  Which disease is a monosomy disorder?
• What is the main difference between euploidy and aneuploidy?

  A)Euploidy refers to an abnormal number of chromosomes, while aneuploidy refers to a normal number of chromosomes.

  B) Euploidy refers to a normal number of chromosomes, while aneuploidy refers to an abnormal number of chromosomes.

  C) Euploidy refers to a condition where there is an extra copy of a specific chromosome, while aneuploidy refers to a condition where there is a missing chromosome.
• Why can the condition of monosomy lead to lethality in an organism?

  A. It leads to the overexpression of certain genes.

  B. It unbalances the genetic material in the organism.

  C. It can unmask recessive lethal alleles that are otherwise tolerated in heterozygotes.

  D. It causes the organism to grow at an accelerated rate.
• Dicentric, Acentric


  When the crossover occurs within a paracentric inversion, one recombinant __________ chromatid (two centromeres) and one recombinant __________ chromatid (lacking a centromere) is produced.
• Which defines chromosomal mutation?

  A. A change in DNA sequence

  B. A change in the structure or number of chromosomes

  C. A change in gene expression

  D. A change in protein structure
• Which is not a molecular function of DNA?

  A. Serves as the blueprint for the synthesis of proteins

  B. Regulate gene expression

  C. Storage and transmission of genetic information

  D. Synthesize nucleotides
• Replication


  It is the process by which a double-stranded DNA molecule is copied to produce two identical DNA molecules.
• Denature


  What will happen if the DNA when the temperature is increased to ~95 degrees.
• Hybridization 


  The process in which two single strands or segments of nucleic acids form a double-stranded structure through hydrogen bonding of complementary base pairs.
• What is the direction of the DNA polymerase during the replication process?

  A. From 5' to 3' direction on a growing DNA strand

  B. From 3' to 5' direction on a growing DNA strand

  C. From 5' to 3' direction on a leading DNA strand

  D. From 3' to 5' direction on a leading DNA strand
• When does DNA replication occur?

  A. During the copying of genes.

  B. During the repair of damage DNA

  C. During S-phase before mitosis and cell division

  D. During the synthesis of mRNA for protein production
• Which is TRUE about DNA replication in prokaryotes and eukaryotes?

  A. DNA replication occurs in the nucleus both in prokaryotes and eukaryotes

  B. DNA replication occurs in the cytoplasm both in prokaryotes and eukaryotes

  C. DNA replication occurs in the nucleus for prokaryotes, whereas in cytoplasm for eukaryotes

  D. DNA replication occurs in the nucleus for eukaryotes, whereas in cytoplasm for prokaryotes
• Polymerase


  Which enzyme is responsible for the synthesis of the long chains of polymers or nucleic acids.
• DNA Recombination


  It defines as the process of rearranging pieces of DNA that creates genetic diversity at the level of genes.
• Homologous end joining repair 


  Which DNA repair mechanism uses an undamaged DNA template on the sister chromatid to repair the break, leading to the reconstitution of the original sequence.
• Non-homologous end-joining repair 


  It is called _____ because the break ends are directly ligated without the need for a homologous template.
• Nucleosome 


  First level of DNA organization where the double-stranded DNA is wrapped around the histone, creating the appearance of "beads" on a string.
• Nucleotide 


  Identify the structure.

  
• Cell


  The smallest unit that is typically considered alive and is a fundamental unit of life.
• Base excision repair


  A DNA repair mechanism which uses DNA glycosylase to remove the damaged base that do not significantly distort the DNA helix structure.
• DNA transposons


  Also known as the "jumping genes" because it can move from one genomic location to another by a cut-and-paste mechanism.
• What is DNA Recombination?

  A. The process of genetic mutation

  B. The exchange of genetic material between non-homologous chromosomes

  C. The process of genetic material exchange between homologous chromosomes

  D. The process of gene expression
• What is the main purpose of DNA recombination in meiosis?

  A. To increase genetic diversity

  B. To reduce genetic diversity

  C. To maintain chromosome number

  D. To increase mutation rate
• Chromosomes


  A unit of inheritance that consist of DNA packaged with proteins.
• Genetic Mutation 


  A change of DNA sequence by removing, adding or replacing pieces of the DNA.
• Loss-of-Function Mutation


  Also known as the null mutation as it reduces or eliminates the function of the gene product.
• Nucleotide


  The basic unit of genetic code
• Which is NOT true about the genetic code?

  A. In every organism, the same sequence of codon codes for the same amino acid.

  B. One amino acid can be coded with one or more corresponding codons.

  C. There are no overlapping codons and no nucleotides interspersed.

  D. The genetic code is universally same with mitochondrial and chloroplast DNA
• What is meant by the “degenerative” genetic code?

  A. More than one codon can encode the same amino acid.

  B. No single codon can encode more than one amino acid.

  C. There are 64 codons with three bases

  D. Genetic code can be used by all viruses, prokaryotes, archaea, and eukaryotes.
• 24


  How many amino acids are coded with the 64 codons?