Prelims BIO 2

• In a human cell, there are two types of DNA: one found in the nucleus and the other found in the mitochondria called mitochondrial DNA
• An organism's genetic material encodes all biological information about the cell
• Humans normally have 23 pairs of chromosomes, with the 23rd pair determining the sex of an individual as either XX for females or XY for males
• Deoxyribonucleic Acid (DNA) is considered the molecular blueprint of life, composed of nucleotides with sugar, phosphate, and nitrogenous bases
• The nitrogenous bases in DNA are adenine, guanine, cytosine, and thymine, which carry the genetic information
• Gene is the unit of heredity in a living organism
• A genome is the genetic complement of an organism, including all its genes
• Genetic Engineering is the process that alters the DNA makeup of an organism, resulting in recombinant DNA
• The 5 tools in rDNA technology are:

  • Restriction Endonucleases to cut
  • Polymerase/DNA Polymerase to create a new strand of DNA
  • Ligase to help bind/glue
  • Vectors to carry and integrate the desired gene
  • Host Organism where the recombinant DNA is introduced, usually bacteria
• Steps in Genetic Engineering:

  • Isolation of the target gene
  • Insertion of the target gene into the vector
  • Introduction of vector into host
  • Amplification of target gene
• Applications of Genetic Engineering:

  • Treatment of genetic diseases
  • Vaccine production
  • Production of medically useful biologicals
  • In agriculture, to create genetically modified crops/organisms
• The ability to reproduce is the process by which new individuals of a species are produced and genetic material is passed from generation to generation
• Two types of reproduction:

  • Asexual Reproduction: offspring produced with only one parent involved, genetic composition is 100% the same as the parent
  • Types of Asexual Reproduction:
  • Parthenogenesis
  • Sporulation
  • Budding
  • Fragmentation
  • Binary Fission
  • Vegetative Propagation
• Sexual Reproduction is the process of producing offspring by the fusion of sperm and egg nuclei to form a zygote
• Embryonic and Fetal Development Strategies:

  • Oviparity
  • Ovoviviparity
  • Viviparity
• Life Cycle of a Flowering Plant:

  • Flowering plants undergo double fertilization
  • In the anther, microspores form pollen grains
  • In the ovule, one megasporocyte produces four haploid megaspores
• Human Reproductive System:

  • Spermatogenesis involves the maturation of sperm cells
  • Stages of Spermatogenesis:
  • Spermatogonia
  • Primary spermatocytes
  • Secondary spermatocytes
  • Spermatids
  • Spermatozoa or sperm
  • Oogenesis involves the maturation of egg cells ready for ovulation
  • Stages of Oogenesis:
  • Primordial germ cells
  • Oogonia
  • Primary oocytes
  • Secondary oocyte
  • Ovum