(Hellman&Carloye) Test Questions and
All Correct Answers.
Independent variable - Answer Value does not depend on another factor
Dependent variable - Answer Value depends on another factor
Controlled variable - Answer Kept the same throughout the experiment
What are the two key tissues that allow plants to transport water or organic nutrients,
respectively, over long distances? - Answer Xylem - water and minerals from roots to shoots
Phloem - transports sugars from photosynthesis to where they are needed
In the root, plants need to take up more CO2 or O2? - Answer More O2
Is the need for CO2 and O2 in leaves the same when compared to roots? - Answer The
difference is because of what the plant needs at that certain spot. The CO2 is needed for
photosynthesis to make sugar for the plant
Why do you think there is/is not a difference in gas exchange when you compare roots with
leaves? - Answer
If you look at the apoplast and the symplast, which of the following statements are true? -
Answer In the apoplastic route water and solute move along the continuum of cell walls and
extracellular spaces
If you add sugar to water does the water potential increase or decrease? - Answer Decrease
How is osmosis defined? - Answer Diffusion of free water
What is a protoplast? - Answer Living part of the cell which includes plasma membrane
,What are rhizobia - Answer They can generate ammonia from atmospheric nitrogen
Why are rhizobacteria beneficial for plants? - Answer They promote growth through chemicals
they produce and they also produce antibodies that protect the roots from disease. Absorb
toxic metals
Why are rhizobacteria beneficial for agriculture? - Answer They can increase crop yield and
reduce the amount of fertilizer and pesticides needed
What is a nodule and what is the reason why they appear sometimes reddish? - Answer It is
composed of plant cells that have been "infected" by Rhizobium. They appear reddish because
of a molecule named leghemoglobin, an iron containing protein that binds reversibly to oxygen.
Similar to the hemoglobin in humans red blood cells
What does the enzyme 'nitrogenase' catalyze? - Answer Atmospheric nitrogen to ammonia
What is the difference between endo- and ectomycorrhizae? - Answer Ecto do not penetrate
the root cortex, whereas endo grow into the invaginations of the root cell membranes called
arbuscules
Do the mycorrhiaze have a symbiotic or mutualistic relationship - Answer Mutualistic
Why have some plants adapted to a carnivorous live style - Answer They lack some of the
minerals so they eat insects. Most of it is because of poor nitrogen in the soil
How many elements have been found in plants, and how many of these are considered to be
'essential'? - Answer 17 and 9 are essential
Based on a plant's dry mass, what are the four most common macronutrients found in plants? -
Answer Carbon, oxygen, hydrogen, nitrogen
How can you distinguish a plant that suffers from phosphorus deficiency versus a nitrogen-
deficient plants - Answer Phosphorus - reddish purple margins
Nitrogen - yellowing of plant at the tip and going towards the center of plant
, What are 'loams', and why is it important for soil to be loamy? - Answer The most fertile
topsoil, it is important because in loams there is enough space to deliver oxygen to the roots.
Made up of sand silt and clay
Why is pH such an important factor for soil quality? - Answer It is important because if the soil
is to acidic then a molecule might bond to the soil to much causing the plant to not be able to
take in the nutrient
Why are cations difficult to get access to in the soil? - Answer They are difficult because they
bond tightly to the soil so another cation has to come break their bond
Clay is negatively charged and tightly bind to cations making it difficult to uptake from soil
What does the term 'cation exchange' means? - Answer Process by which cations are
displaced from soil particle by other cations
Are anions also difficult to take up from the soil by plants? - Answer They are easier to take up
from the soil but harder to come by do to being lost during leaching because they do not bond
to the negatively charged soil ions
What does the term heterospory means? - Answer production of spores of two different sizes
and sexes by the sporophytes of land plants.
What defines an ovule - Answer Female gametophyte
What are the advantages of having reduced gametophytes? - Answer Gametophytes can
develop from spores and be shielded from UV light. This also allows the dependent
gametophytes to gain nutrients from the sporophyte.
What are the evolutionary advantages of a seed? - Answer Seed are multicellular, a seed can
be dormant for a long time, supply of stored food
How does the role of the sporophyte change if you go from lower land plants (bryophytes) to
higher land plants (e.g. gymnosperms or angiosperms)? - Answer Sporophytes in lower land
plants is more for reproductive purposes
What is the difference between an ovary and an ovule - Answer The ovary holds the ovules