Study topics for Test 2
Topics covered: # 4, 5, 6 and 7.
Note from 9/30/2005. This is the complete final list of the
study topics.
- Name 12 major soil orders. Give an example of a typical soil type for
the following biomes: 1) tropical rainforest; 2) deciduous hickory-oak
forest (e.g. as in North Carolina); 3) desert; 4) tundra. Explain how
prevailing climatic conditions in each of these 4 biomes, and texture
and mineral composition of each type of these 4 types of soils will affect
their stratification and fertility.
- Give examples of adaptations which tropical rainforest plants have
developed to grow on low fertility soils. Define epiphytes and mycorrhizae.
- Give definition of Darwinian adaptation. Give examples of biochemical,
morphological, physiological and behavioral adaptations to the environment
(you can draw examples from this course or any other biology courses).
- Give definition of natural selection. Explain what genotype and
phenotype is. Explain how selection can increase frequencies of
particular genes through acting on phenotype.
- What are the 4 main assumptions of theory of natural selection?
- Define Darwinian fitness. Be able to calculate fitness of a genotype if
given the total number of offspring produced, and number or % of
offspring surviving till maturity for all genotypes in the population. What
is the maximum and minimum value of Darwinian fitness?
- Explain how difference in fitness between different genotypes will
result in an increase or decrease of frequency of corresponding alleles in
the next generation. Be able to determine from the fitness of different
genotypes , which allele will increase in frequency with time in a
population.
- Describe two major types of trophic biology of organisms. Define
autotrophs and heterotrophs. What are sources of energy and carbon for
autotrophs and heterotrophs? How are autotrophs further classified based on
their energy source?
- Explain how different types of trophic biology are distributed among the
5 major biological kingdoms. Give examples of chemosynthetic autotrophs ,
photosynthetic autotrophs and heterotrophs for those kingdoms that have more
than 1 type of trophic biology.
- Define PAR and give wavelength for PAR. What are the absorbance maxima
of the chlorophyll a? Why terrestrial plants appear green in color?
- Give summary reactions for light-dependent and light-independent parts
of the plant photosynthesis. Explain in which part of the photosynthesis
carbon fixation occurs, and in which - production of sugars from simple
organic molecules.
- Compare C3, C4 and CAM pathways of photosynthesis. Draw simplified
pathways for all 3 types of photosynthesis including the following compounds
(as appropriate): RUBISCO, RuBP, C3 compounds (e.g. PGA), C4 acids
(e.g. malate or aspartate), PEP, PEPCK, simple sugars (don't forget to
indicate the role of RUBISCO, RuBP and C3 compounds in C4 and CAM
photosynthesis!). Indicate which part of the pathway corresponds to
the light dependent and light-independent reactions and state where and when
these reactions occur a in each type of the photosynthesis.
- What are key enzymes responsible for initial fixation of atmospheric CO2
in C3, C4 and CAM pathways of photosynthesis? Compare the properties of
these enzymes: affinity for CO2, propensity to catalyze photorespiration.
Define photorespiration.
- Explain how different pathways of photosynthesis allow plants to survive
and reproduce in different types of the environments (wet and cool vs hot
and dry). Explain the role of C4 and CAM pathways for water conservation by
plants.
- Explain how plants adapt to different light intensity. Define and
explain light compensation point and light saturation point. Which
physiological process in plants causes CO2 release? Which physiological
process causes CO2 uptake?
- How do light compensation point and light saturation points differ
between sun-loving and shade-tolerant plants? Be able to determine which of
the 2 plant species is more shade-tolerant if given values of light
compensation or light saturation points for these 2 species.
- Define light attenuation and explain how wavelength of PAR change with
increasing depth in aquatic environments. What is euphotic zone and how deep
it is in different parts of the ocean or large lakes (coast vs open waters)?
- Explain how different pigments allow algae and cyanobacteria to grow in
deep waters. Why are chlorophyll a-containing plants unable to survive in
deep waters?
- Define water potential in the soil and in plants. Explain what is a
cohesion theory of water transport in plants. How does water evaporation
from plant foliage assist in water transport?
- Explain how water potential determines the direction of water flow
between soil and plant roots (I will give you values of water potential in
the soil and the plant roots and ask you to determine whether water uptake,
water loss by the plant or no water movement will occur).
- In which 2 states of the soil the water potential in the soil is higher
than the water potential in plants? In which 2 states of the soil the water
potential in the soil is equal to or lower than the water potential in
plants? In which of those 4 states is the water uptake by plants possible
and when it is not?
- List major macronutrients required for plant growth. Using example of
nitrogen, explain how the rate of nutrient uptake depend on the
concentration of the nutrient in the soil.
- Describe how the rate of photosynthesis of a plant depend on the rate of
N uptake. Be able to draw a typical saturation curve and to determine
saturation point for the curve. Compare saturation curves of the plants
adapted to soils with high and low N concentrations.
- List 3 major physiological and morphological adaptations of plants to
low-nutrient conditions (growth rate, root morphology, leaf longevity) and
explain how they help plants survive when soil levels of bioavailable
nitrogen are low.
- Define temperature and explain why temperature has a strong effect on
the rates of all chemical (including biochemical) reactions.
- Explain what is Q10. Give the range of typical Q10 for physiological and
biochemical reactions.
- Explain how the interaction between rate-enhancing and damaging effects
of temperature determines the thermal optimum of a species. Name proteins
which can provide partial protection against heat-induced protein
denaturation. Define optimum temperature.
- Compare thermal optima and windows of thermal tolerance in
organisms living in different environments; how they relate to the
prevailing temperature regime in the environment? Define stenotherms and
eurytherms; give examples.
- Explain how organisms can use external and internal sources of heat to
regulate their body temperature. Write down the equation of thermal balance
of an organism. Based on this equation, explain how different physical and
biochemical processes may be used for the maintenance of body temperature
and heat balance. Define conduction, convection, radiation, metabolic heat
production and evaporation and explain their role in regulation of body
temperature.
- Define ectotherms and endotherms; poikolotherms and homeotherms; give
examples of animals for each of the 4 combinations (ectothermic
poikilotherms; ectothermic homeotherms; endothermic homeotherms; endothermic
poikilotherms).
- Compare mechanisms of regulation of body temperature in a typical
endothermic homeotherm (e.g. a mammal) and a typical ectothermic
poikilotherm (e.g. in a reptile).