AP BIO CRAM

• Cell


  The basic unit of life, surrounded by a cell membrane, containing genetic information and cytoplasm
• Genome


  The entire set of genetic material or biological instructions for an organism
• Gene


  A unit of the genome that codes for a specific protein
• Signal Transduction Pathway


  A pathway involving signal reception, a signaling cascade, and a response, often involving gene expression, hormone production, or apoptosis
• Protein Synthesis


  1. DNA template read by RNA polymerase to produce mRNA

  2. mRNA transported to ribosome

  3. tRNA brings amino acids to ribosome to build polypeptide chain

  4. Protein undergoes further modifications
• Operon


  A group of genes in prokaryotes that are controlled together, can be induced or repressed
• Introns and Exons


  Non-coding and coding sequences in eukaryotic genes, introns are removed during RNA processing
• PCR is the amplification of DNA, gel electrophoresis separates DNA by size, DNA sequencing determines the order of nucleotides, and bacterial transformation inserts foreign DNA into bacteria
• Biological Macromolecules


  • Nucleic Acids
  • Proteins
  • Carbohydrates
  • Lipids
• Cellular Respiration


  Glycolysis in cytosol, Citric Acid Cycle in mitochondrial matrix, Electron Transport Chain in inner mitochondrial membrane
• Photosynthesis


  Light-dependent reactions in thylakoid membranes, Calvin Cycle in stroma
• Feedback Loops


  Negative feedback loops maintain homeostasis, positive feedback loops amplify a process
• Enzymes denature at high temperatures, water has unique properties like high heat of vaporization, small non-polar molecules can freely cross cell membranes
• Key Organelles


  • Cell Membrane
  • Nucleus
  • Mitochondria
  • Chloroplasts
  • Endoplasmic Reticulum
  • Golgi Apparatus
  • Lysosomes
  • Ribosomes
• Small non-polar molecules


  Can freely pass through membranes (e.g. carbon dioxide, oxygen)
• Cell membranes


  Allow cells to establish and maintain internal environments different from external environments
• Internal membranes


  Help with different cellular processes, minimise competing interactions, increase surface area for reactions
• Internal membranes provide evidence for the endosymbiosis hypothesis
• Organelles important for AP Biology

  • Cell membranes
  • Mitochondria
  • Chloroplasts
• Cell membranes


  • Complex, beyond just a phospholipid bilayer
  • Have integral proteins for transport, support, cell surface reception, cell identification, and other activities
  • Contain carbohydrates and cholesterols
• Mitochondria and chloroplasts


  Important for cellular energetics (cellular respiration and photosynthesis)
• Mitochondria have their own DNA, unlike nuclear DNA which can come from both parents, mitochondrial DNA is only inherited from the mother through maternal inheritance
• DNA structure


  • Each nucleotide has a phosphate, sugar, and base (A, T, G, or C)
  • A and T pair with hydrogen bonds
  • G and C pair with hydrogen bonds
  • Backbone is made of phosphate and sugar molecules
• RNA


  Single-stranded, has structural similarities to DNA but with ribose sugar and uracil base instead of thymine
• Cell cycle


  • Has internal controls and checkpoints that regulate progression
  • Errors can lead to uncontrolled cell growth and disease like cancer
• Mitosis


  Produces two genetically identical daughter cells
• Meiosis


  1. Produces cells with half the normal amount of genetic material (gametes or sex cells)

  2. Contributes to genetic diversity through independent assortment, random fertilization, and crossing over
• Water movement


  Water moves by osmosis from areas of high water potential to areas of low water potential
• Inheritance patterns


  • Single gene/monohybrid inheritance
  • Dihybrid inheritance
  • Sex-linked inheritance
  • Genetically linked inheritance
  • Mitochondrial DNA inheritance
• Environmental impacts


  Can influence molecular functions and gene expression
• Environmental pressures


  Can strongly influence natural selection
• Biodiversity


  Increased biodiversity in an ecosystem increases resilience
• Thermoregulation strategies


  • Endotherms (use metabolism to generate warmth)
  • Ectotherms (depend on environment to regulate temperature)
• Smaller organisms


  Have higher metabolic rates and energy needs
• Trophic levels


  • Organisms consume others to gain energy
  • Net energy gain results in growth and survival, net energy loss results in death
• There is about a 90% energy loss at each trophic level
• Domains of life


  • Bacteria
  • Archaea
  • Eukarya
• Phylogenetic tree/cladogram


  • Visualizes relationships between organisms
  • Branching lines represent evolutionary relationships
  • Hash marks represent evolved traits
• Biochemical, embryonic, fossil, and morphological evidence helps determine organism relationships and evolution
• Evolution


  • Change in genetic makeup of a population over time, not just change in individual organisms
  • Variation within populations allows natural selection to occur