gen. physiology final

• Physiology


  The study of function (fundamental branch of biology)
• Why study physiology


  • Understand energy usage, production, and cost
  • Understand relationship between chemistry and biology
  • Understand how genes —>proteins —>cells —> tissue —> bodies
  • Understand health and bodily errors and how to fix them
  • Relates to all other branches of biology (anatomy, ecology, cellular, biochem, evolution, genetics)
• Types of physiology


  • Mechanistic
  • Evolutionary
  • Comparative
  • Environmental
  • Integrated
• Mechanism


  The components of organisms and how those components interact to allow the organism to function as an organism
• Evolution


  A change in gene frequencies over time in a population
• Evolution


  • Can result in adaptation, or it can be nonadaptive
  • Highly dependent on population size and genetic diversity of that population
  • A small population with less diversity will evolve quicker than its opposite
  • The greater the stresser, the higher the chance of nonadaptive evolution
• Natural selection


  The increase of genes (alleles) in a population that produce a specific type of phenotype that increases survival in a specific environment
• Adaptation


  A genetically controlled trait that, through the process of natural selection, has come to be present at high frequency in a population because it confers a greater probability of survival and successful reproduction in the prevailing environment than available alternative states
• Adaptations


  • Are net positives for organisms
  • Takes long amount of time and even generations to happen
• Nonadaptive evolution


  Evolution that occurs by processes other than natural selection and that therefore can produce traits that are not adaptations
• Genetic drift


  Changes in gene frequency in small populations due to chance
• Pleiotropy


  The control of two or more unrelated phenotypes by an allele of a single gene
• Points of study in physiology


  • Structural dynamics
  • Bodily organization and energy usage
  • Development and aging
• Conformity


  Aspects of an organism that match the external environment
• Regulation


  Aspects of an organism that are maintained differently than the external environment
• Homeostasis


  The tendency towards stability of internal environmental aspects
• Physiological change time scales


  • Acute
  • Chronic
  • Evolutionary
  • Developmental
  • Periodic biological clock
• Scaling


  The study of the relationship between physiological/morphological aspects and body size within phylogenetically related species
• Major environmental aspects


  • Temperature
  • Oxygen
  • Water
• Microclimates are climate conditions specific to specific subparts of a larger environment
• Desert animals must deal with extreme heat and cold
• Subnivean air space allows small tundra animals to live in a air gap between the snow and grass beneath it
• Animals can also modify the environment like deer overpopulation in Yellowstone in the 90s
• Hemoglobin


  Central iron II ion and two pairs of α and β globulin protein-units
• Icefish lack β globulin gene and part of α globulin gene, which was disadvantageous but they compensated with larger hearts and faster circulation
• Myoglobin was lost independently in three different ancestors of icefish through three different mutations of the same gene
• All ice fish have antifreeze glycoprotein, which was evolved in a common ancestor to all arctic/antarctic fish
• Phylogenetic tree


  Each diverging point is a common ancestor, and each diverging line represents a major mutation
• Top down vs. Bottom up

  Top: full body function to cellular function

  Bottom: genes (genomics) ->(transcriptomics)
• Top down approach


  • Allows for broad and macro understanding of physiology

  Allows for honing on specific causes of each level of function
• Bottom up approach


  • Requires High-throughput methods, so data will be very detailed and specific

  Reduces biases from expected outcomes due to knowledge of similar phenotypes and genotypes
• Genetics terms


  • Genotype
  • Phenotype
  • Transcription
  • Epistasis
  • Epigenetics
  • Upregulation
  • Downregulation
  • Overexpression
  • Silence
  • Translation
  • Transcription factor
  • Intron
  • Exon
  • Spliceosomes
  • mRNA
  • Mutation
• Genomics


  The study of the genome, the full set of genes and genetic material of an organism
• Goals of genomics


  • Describe the evolution of genes

  Describe the function of each gene
• Gene families


  Groups of homologous genes (share similar base sequences) that are likely to have highly similar functions
• Gene deletion or gene knockout


  Using epigenetics and CRISPR, remove or silence a gene and see what happens
• Transcriptomics


  The study of DNA transcription, which is affected by up and down regulation, epistasis and epigenetics
• DNA Microarrays


  Compares two samples of DNA by extracting mRNA, staining with different fluorescent pigments, and seeing which genes are expressed in each sample
• Proteomics


  The study of translation and how proteins affect cells, tissues, and the body
• 2D gel-electrophoresis


  One way pulls the protein sample by isoelectric point, the other by molecular weight, to study protein concentration and function