Bio exam 1

• The nucleus is the control center of the cell.
• Living things have 

  • Organization 
  • Evolution of populations
  • DNA
  • Reproduction
  • grown/development
  • Response to environment 
  • Metabolizm
  • Homeostasis
  • Contains one or more cells
• Viruses aren't living. They reproduce, but only in a host, they have RNA, and they evolve but they dont have…

  • Organization
  • Growth
  • Response to environment 
  • Metabolism 
  • Homeostasis
  • Cells 
• Sars-CoV2 is a Single stranded RNA virus 

  • Enters human cells via ACE 2 receptor 
• 1. cell theory.

  • All organisms have cells 
  • Cells are building blocks 
  • Cells come from other cells 
• 1.  the 3 domains of life.

  • Bacteria (prokaryotes) 
  • Archaea (prokaryotes) 
  • Eukarya (eukaryotes, including protists) 
• Evidence used to reclassify organisms into the 3 domains was rRNA since all living things have ribosomes 
• Protists are eukaryotic organisms that are not plants or animals.
• Prokaryotic: 

  • No nucleus 
  • Small

  Eukaryotic: 

  • nucleus/organelles 
  • Larger 
  • Carry out endo/exocytosis 
• 1. Explain why cell size is limited.

  • Limits in resource availability
  • SA to V ratio 
• 1. Explain the strategies cells/organisms can use to overcome the limitations imposed by surface area:volume constraints.

  • Growth stops 
  • Cells divide 
  • Membrane folding/different shapes Active transport 
  • Multicellularity 
• 1. Define the following types of cells/tissues: epithelial, endothelial.

  Epithelial cells- cells lining structures 

  Endothelial cells- cells lining the cardiovascular system 
• 1. Describe how cells are fractionated in order to study their individual components. What does is mean to "lyse" a cell? What is homogenization? What is centrifugation?

  • Cell lysis: cells are broken open 
  • Homogenization: blended 
  • Centrifugation: spun to separate components 
• 1. Define the sedimentation coefficient and explain its usage in cell biology.

  • larger/denser= higher S value 
  • Usd to indicate relative size 
• 1. Describe the structure/function of the various subcellular structures of prokaryotic and/or eukaryotic cells that we discussed today (i.e. extracellular matrix, cytoplasm, nucleus, etc...).

  Plasma membrane: defines the cell and regulates what goes in and out 

  ECM: network of fibers outside the PM that supports structure and adhesion 
• 1. Define "peptide".

  Short chains of amino acids 
• 1. Describe the Gram stain and its purpose. 

  Done to ID bacteria 

  Positive: CW traps the violet dye (thick peptidoglycan) 

  Negative: CW is thinner and cells appear pink 
• Nucleus:

  • Stores DNA
• Nuclear lamina:

  • Supports nuclear structure
• Nuclear pores:

  • Controls movement in and out of the nucleus
• Nucleolus:

  • Site for ribosomal subunit synthesis
• Prokaryotic ribosome:

  • Large subunit: 50s
  • Small subunit: 30s
  • Full ribosome: 70s
• Eukaryotic ribosome:

  • Large subunit: 60s
  • Small subunit: 40s
  • Full ribosome: 80s
• Smooth ER:

  • Functions in lipid synthesis, carbohydrate metabolism, calcium storage, and detoxification
• Rough ER:

  • Produces glycoproteins
  • Modifies proteins
• Golgi:

  • Modifies products of the ER
  • Sorts and packages proteins
• Lysosomes:

  • Contain hydrolytic enzymes for digestion
• Vacuoles:

  • Store nutrients and enzymes
• Mitochondria:

  • Site of cellular respiration (evolved from proteobacteria)
• Chloroplasts:

  • Site of photosynthesis (evolved from cyanobacteria)
• Peroxisomes:

  • Break down H2O2
• • Phagocytosis: ingestion of large particles 
  • Authophagy: degradation of old/damaged cells 
• 1. What is the "lumen" of an organelle?

  Inside of it
• 1. What is "symbiosis"?

  • Peaceful coexistence 
• 1. Explain the endosymbiotic theory for the origin of mitochondria and chloroplasts.

  • They originated as free-living prokaryotes 
  • Smaller prokaryotes engulfed by larger 
• 1. Provide evidence in support of the endosymbiotic theory. Describe "horizontal gene transfer", and how it relates to the endosymbiotic theory.

  • Similar size to prokaryotes 
  • Replicate by binary fission 
  • Double membrane 
  • Have their own 70s ribosomes 
  • Have their own genome 
  • Horizontal gene transfer
• 1. Distinguish the various types of macromolecules found in living things. 

  • Carbs 
  • Nucleic acids
  • Proteins 
• 1. Identify and describe the monomer units used to construct the polymeric macromolecules.

  • Carbs- monosaccharides
  • Nucleic acids- nucleotides 
  • Proteins- nucleic acids 
• 1. Describe the process by which polymers are synthesized and the process by which polymers are broken down in cells.

  • Occurs by condensation (removal of water to synthesize polymers)
  • Occurs by hydrolysis (addition of water to breakdown polymers) 
• 1. Describe in general the properties of lipids. What are the functions of lipids? How are they different from the other types of macromolecules that make up cells?

  • Lipids are hydrophobic 
  • They provide long term energy storage 
  • They provide protection 
  • They regulate the body and help in signaling 
  • They help metabolite vitamins