Bio 1106 Final Exam

• Compare and contrast the sporophyte and gametophyte generations in the alternations of generations life cycle


  1. Haploid

  2. Spores develop into gametophytes

  3. Gametes produced by mitosis

  4. Diploid

  5. Fertilization

  6. Zygote grows into sporophyte

  7. Spores produced by meiosis
• Evolutionary advantages of seeds


  • Protection of embryo
  • Dormancy
• Explain the function of meristems and the role meristems play in primary and secondary growth


  1. Primary/Apical= growth in length

  2. Secondary/Lateral=growth in diameter

  3. Vascular cambium

  4. Secondary xylem = wood

  5. Secondary phloem

  6. Annual growth rings
• Roots


  • Root hairs on surface increase surface area
  • Tap roots and fibrous roots anchor well
• Function of roots


  • Anchor the plant
  • Absorb water/minerals from soil
• Stems


  • Vascular tissue and collenchyma in ground tissue provides support
• Function of stems


  Support leaves and reproductive structures
• Leaves


  • Mesophyll cells in chloroplasts
  • Stoma for gas exchange
• Function of leaves


  Primary site of photsynthesis
• Layers in a cross section of a woody stem


  • Cork cambium
  • Cork cells
  • Phelloderm-parenchyma
  • Periderm- cork cambium +cork + phelloderm
  • Bark
  • Lenticels
• Explain the cohesion-tension theory of water transport in the xylem

  1. Driving force for transport=transpiration

  2. Water moves from higher water potential to lower water potential
• Explain the pressure flow hypothesis of fluid transport in the phloem

  1. Movement of carbs in the phloem

  2. Carbs move from sources to sinks

  3. Phloem loading: active transport, requires energy
• Nutritional requirements of plants

  • Carbon
  • Hydrogen
  • Oxygen
  • Phosphorus
  • Potassium
  • Iodine
  • Nitrogen
  • Sulfur
  • Calcium
  • Iron
  • Magnesium
• How plants extract nutrients from the soil

  1. Soil particles have negative charge, positive ions attracted to soil particles

  2. Negative ions stay in solution surrounding roots which creates a charge gradient that pulls positive ions out of root cells

  3. Active transport required to maintain potassium and other positive ions in the root
• Defensive features of the plant dermal tissue


  • Wax
  • Cutin
  • Suberin
  • Silica inclusions
  • Trichomes
  • Bark
  • Thorns
• How carnivorous adaptations, parasitism, and mutualism can improve nutrient acquisition


  1. Carnivorous adaptations: modified leaves, hairs, and trichomes to trap insects, nitrogen

  2. Parasitic plants: exploit "host" for nutrients, carbohydrates

  3. Mutualism: not very common, mostly in plants from bean family
• Chlorophyll


  Used to capture light energy
• Phytochrome


  Red (Pr, inactive)/far-red light (Pfr, active)
• Plant responses to phytochrome


  1. Long night: no Pfr at dawn

  2. Short night: more Pfr at dawn

  3. Seed germination: sunny conditions promote buildup of Pfr
• Phototropism


  Directional growth in response to light, shoots positively phototropic
• Gravitropism


  • In response of plants to the gravitational field of the Earth
  • Positively gravitropic: roots bend towards center of gravity
  • Negatively gravitropic: stems bend away from center of gravity
• Complete flower


  • All 4 whorls
  • Stamens, carpels, petals, sepals
  • Attract pollinators
• Microgametophytes


  Male, pollen grains
• Megagametophytes


  Female, embryo sac
• Co-evolution between flowers and pollinators

  The flowers that needed pollinators became more colorful/stand out more in order to attract the pollinators
• Pericarp


  Ovary wall
• Hierarchal organization of the animal body

  • Cell
  • Tissue
  • Organ
  • Organ system
  • Organism
• Types of animal tissues


  • Epithelial
  • Connective
  • Muscle
  • Nervous
• Homeostasis


  Stable operating conditions in the internal environment
• Negative feedback


  Response counteracts the original change (e.g. temperature regulation in the body)
• Positive feedback


  Response intensifies original change (e.g. birth in mammals)
• Modes of temperature regulation

  • Endotherms: internal heat generation, metabolic heat, insulation
  • Ectotherms: external sources of heat, rely on environment for heat, little to no insulation
• Structure of a neuron


  • Cell body: contains nucleus where information is integrated
  • Dendrite: receive electrochemical information from multiple different sources simultaneously
  • Axon: when electrochemical signal is sufficient, a conduction of impulses is triggered ad travels away from cell body
  • Myelin sheath: layer of insulation around the axon
  • Shawann cell: make up layer of insulation in myelin sheath, wraps around axon to form myelin sheath
  • Node of Ranvier: conductive gaps that speed up the transmission of a signal
• Subdivisions of the vertebrate nervous system

  • Central nervous system: brain and spinal cord interneurons
  • Peripheral nervous system: sensory and motor neurons
• Types of neurons

  • Sensory neurons: bring signals into the central nervous system
  • Motor neurons: carrying signals out of the central nervous system
• Types of motor neurons

  • Somatic motor neurons: voluntary movements
  • Autonomic motor neurons: involuntary movements
• Subdivisions of the autonomic nervous system

  • Sympathetic NS: fight or flight
  • Parasympathetic NS: rest and repose
• Ionic basis of the resting membrane potential, action potential, and synaptic potentials

  1. Resting membrane potential: neuron membrane also has more potassium leakage channels than sodium leakage channels making the membrane more permeable to potassium than to sodium. Potassium will diffuse out of the cell due to the concentration gradient. The combination of increased permeability to potassium and the actions of the sodium potassium pump results in the build up of charge differences across the cell membrane known as the resting potential

  2. Action potential: signals that propagate down the axon

  3. Synaptic potentials: potentials across a synapse

  4. Ligand gated channels: lead to graded potentials, open to in response to chemical stimulus

  5. Voltage gated channels: lead to action potentials, open in response to changes in membrane potential
• Inhibitory neurotransmitters


  Hyperpolarize postsynaptic cell
• Stimulatory neurotransmitters


  Depolarizes a excitatory neuron