Plant Life Cycles
True or False: Some plants are characterized by alternation of diploid and haploid generations
False; All plants go through alternation of generations
Would the surface area of leaves change according to location?
Yes!
Provide an example
What are the inputs and outputs of photosynthesis?
Input: light energy, carbon dioxide, water
Output: oxygen, carbohydrates (glucose/starch)
What were the first land plants like?
small, low, spread out,
What do leaves do?
They are the primary site of photosynthesis
What do sporophytes produce?
What do gametophytes produce?
Do all plants have growth rings?
No!
Provide an example of one that does and does not
True or False: Gymnosperms have motile sperm that require water for reproduction
False: Vascular seedless plants and non-vascular plants have this characteristic; gymnosperms have cones that produce seeds for reproduction
What are the two pigments that give plants their green color?
chlorophyll a and chlorophyll b
What is a cuticle?
a waxy layer on the outer part of leaves to prevent water loss
Which plant contains fruit that develops from the ovary?
Angiosperms
What do xylem and phloem do?
Xylem: transports water and dissolved nutrients; provides the plant with structural support; flows upward in one direction
Phloem: Transports sugars and many nutrients; does not provide support; flows both upward and downward
Why are plants important?
Which major group(s) of plants require water in order to reproduce?
Nonvascular plants and vascular seedless plants; their sperm need water to swim
What major plant group do ferns belong to?
Vascular seedless plants
What of the four categories of plants are only sporophyte dominant?
Vascular Seedless Plants
What are the two phases of plant growth? What occurs at each phase?
Primary growth: herbaceous plant body; extends the plant length (height/depth)
Secondary growth: woody plant body; increase plant girth and provide support and additional vascular tissue
What are four examples of stressors faced by plants? How do they affect plants?
1. Wind: can directly damage plant tissues; increases transpirational loss of water
2. Aridity: increases transpirational loss of water
3. Temperature: disrupts cellular functions; increases transpirational loss of water
4. Heterogeneity of resources: resources are not distributed evenly across environment
What are some innovative structures that plants have developed?
Modified leaves (for protection, light absorption, etc.)
Roots (for water and nutrient absorption, anchorage, etc.)
Vascular tissue (for transportation of water, minerals, proteins and sugars up/down the plant and support)
Flowers/fruit (for attracting pollinators and spreading seeds)
Wood (more structural support, ability to grow taller and wider [secondary growth])
Other possible answers: pollen, spores, cuticle, etc.
From the two photosynthesis systems, we have learned what they are, which one is more "expensive," and why.
C3 and C4 Photosynthesis
C4 is more expensive because it requires more ATPs to make sugar
Explain what occurs at each step of the general cycle of alternation of generations in plants
What are the two types and root structures? Explain the differences between them.
Fibrous Roots:
-Similarly sized roots all branching out from the stem
-Tend to occupy the upper, shallow parts of the soil, and spread outwards
Taproots:
-Thicker primary roots with many smaller roots branching out from them
-Often grow deep down into the soil
-May store sugars as starch
Compare and contrast vascular seedless plants and angiosperms
Vascular seedless plants have vascular tissue and motile sperm that require water for reproduction. They live an evenly split life cycle between gametophyte and sporophyte.
Angiosperms have vascular tissue, can produce seeds that are enclosed in fruit, and can have flowers. They live a sporophyte-dominated life cycle.
What are the 3 gases that pass through this "pore" in the cuticle and epidermis of the plant?
(Answer should include what the "pore" is named and the 3 gases)
Stomata --> CO2, H2O, & O2
Explain the process of CAM photosynthesis
Night Time:
Stomata is open. Exchange of gases with the atmosphere
-CO2 fixed into 4-carbon organic acid
-Water loss is minimized
Day Time:
Stomata closed. Calvin cycle converts CO2 (from acid) into 3-carbon organic molecule