Midterm 1 Practice Questions Flashcards
When is a mineral deficiency likely to affect older leaves more than younger leaves?
When the mineral is mobile
What are two types of symbiotic associations seen in plants that increase nutrient uptake?
Mycorrhizal fungi and nitrogen fixing bacteria (rhizobium)
Where are the sites of starch and sucrose synthesis in plants?
starch: chloroplast
sucrose: cytoplast
What does it mean for photosynthesis to be ‘light limited’
Photosynthesis is light limited when the limiting factor for production of sucrose is light., meaning that an increase in the amount of light directly relates to an increase in the rate of photosynthesis
Group 1
Nutrients that are part of carbon compounds: Nitrogen and sulfur
Group 2
Nutrients involved in energy storage and structural integrity: phosphorus, silicon & boron
Group 3
Nutrients that remain in ionic form: Mg, K, Ca, Cl, Mn, &Na
Group 4
Nutrients important to e- transfer:
Fe, Mo, Zn, Cu, Ni
2 roles of secondary metabolites
Defense and pollinator attraction
Glutamate is better for…
immediate synthesis in high light conditions because it has a higher C:N ratio (more C than N)
Asparagine is better for…
Storage/low light conditions because it has a lower C:N ratio. This affects the pathway because low energy conditions stimulate asparagine synthetase
What effect does light intensity have on C3 plants?
High light intensity means that photosynthetic activity is increased. This means that there is more oxygen produced at PS2, and thus increases the oxygenase activity of Rubisco. This waste of energy decreases yields of C3 plants.
What effect does light intensity have on C4 plants?
High light intensity conditions in C4 plants will increase the activity of the photosystems, and PS2 will create more oxygen. Although this would cause problems in C3 plants, the physical separation of Rubisco from the photosystems prevents it from oxygenation activity over carboxylation
