Possible Short Answer Questions (Plants)

What is the typical function of a plant's root system?

Anchors the plant and takes in water and nutrients from the soil

Identify two general classes of pollen vectors; give an example of each

Biotic: Bumblebee Abiotic: Wind

Compare the cohesion-tension theory (also called the transpiration-cohesion-tension theory) for water movement and the pressure-flow model for phloem sap movement in plants

CT: Water is pulled to the tops of the trees along a water-potential gradient via forces generated by transpiration at leaf surfaeces PF: Events at source tissues and sink tissues create a pressure potential gradient in phloem Based on movement along water-potential gradient Differences between turgor pressure in phloem near source and sink tissue Usually requires ATP

Use an arrow diagram to arrange soil particles (clay, sand, silt) in order of increasing size (smallest to largest)

Clay Silt Sand

What is the importance of the clay component of soil?

Clay retains nutrients better and hold water better than sandy soils. Clay makes cations more difficult for plants to extract bc cations are bound tightly to clay.

Describe the function of the following: flower, petal, fleshy fruit, seed dormancy

Flower: A reproductive structure that produces gametes, attracts gametes, nourishes embryos, and develops seeds and fruits Petal: advertise the flower to pollinators Fleshy Fruit: Animal dispersion Seed Dormancy: seeds do not germinate for a long period of time to make sure environmental conditions are right

Compare generalist and specialist pollinators

Generalist pollinate all species while specialist pollinators stick to one

What is the typical function of a plant's shoot system?

Harvests light and CO2 from the atmosphere to produce sugars

What is the benefit of carnivory for plants?

Make their own carbohydrates via photosynthesis but use carnivore to supplement the nitrogen available in the environment

Describe alternation of generation in plants

Meiosis does not lead directly to the formation of gametes. Leads to the production of haploid cells called spores

Identify factors that affect a water potential gradient

Solutes, root pressure, capillary action

Identify two (leaf;stem) modifications and the functions of the modified (leaves;stems)

Stem: Cacti: large water storage organs Stem: Thorns: help protect plants by attacks from herbivores Leaves: Succulents: store water Leaves: Poinsettias: attract pollinators

Identify adaptations that allow plants in arid (dry) environments to limit water loss

Thick cuticle covers the surfaces (waxy layer) Stomata are located on undersides of leaves (slow loss of water vapor)

Describe the direction in which water moves relative to its water potential gradient

Water moves from areas of high water potential to areas of low water potential. Highest in soil, lower in roots, lower more in leaves, lowest in atmosphere