Test 3 Flashcards

Question

Alternate photosynthesis:

Answer 1

a. PEP carboxylase: both C4 and CAM plants use this for carbon fixation i. sticks CO2 onto PEP compounds (PEP = phosphoenol pyruvate) ii. PEP (3C) + CO2 (1C) -> oxaloacetate (4C) -> malate (4c) 1. The malate can be decarboxylated (released CO2) back into PEP

Answer 2

a. Tropic plants only in calvin cycle b. Big cells are bundle sheath cells next to veins (kranz anatomy) i. spatial separation of C fixation c. PEP carboxylase (PEP +CO2 -> malate) malate and CO2 diffuse into the bundle sheath cells (increases the CO2 concentration) and the CO2 is released into the Calvin-Benson Cycle

Answer 3

a. arid plants b. can decided what photosynthesis to undergo (C4 or C3) c. close stomata in daytime and open in nighttime i. temporal separation of C fixation d. Night: PEP +CO2 -> malate -> malic acid (stored in vacuole) e. Day: malic acid (decarboxylated) -> malate (releases CO2), CO2 goes to fuel Calvin Benson cycle

Answer 4

Water transport happens in the xylem tissue from root to shoot - Xylem tissue composed of xylem fibers (dead; structure) and xylem parenchyma (alive; storage). Vessel elements (wide/short/open walls) and tracheids (long/narrow/tapered walls) are responsible for conducting water and minerals apoplectically (outside) throughout the cell and both are dead at maturity

Answer 5

- Moving lot of water long distances - Passive process and requires no energy for the plant - 120-15K cm/hour (vines) - 40L gallons/year (oak tree)

Answer 6

Pulling of water through the xylem and can only work because of the tension between the hydrogen bonds in water - Water movement in the xylem is unidirectional root to shoot - Soil water moves through the roots, up through the xylem, into the leaves, and out through stomata into the atmosphere - Xylem is the drinking straw, drink is the water in the sale, and the person drinking is the atmosphere - Passive process that doesn't require energy input - 96% of water that moves through a plant is lost into the atmosphere through transpiration - water is a limiting source

Answer 7

Air bubble that forms in the xylem (breaking the water column)

Answer 8

- Pair of guard cells that regulates gas exchange and transpiration of water out of the leaves. Pressure determines the shape of the cell - Inner portion: cellulose is laid down very thick and ridged - Outer part: cellulose is laid down very lose and stretchy

Answer 9

Higher pressure inside the cells. Need water to move in to increase turgid pressure. Potassium concentration is high inside the cell; K moves into the cell and makes the cell bend

Answer 10

Lower pressure inside the cells. Need water to move out to decrease turgid pressure. Potassium concentration is low outside the cell; K is exported of the cell and makes the cells collapse on each other

Answer 11

Open: Cellulose is thick around middle portion; the outside is stretchy; outside swells and middle does not when you increase the turgid pressure in the plant. Closed: inside is ridged, outside is stretchy. When water rushes in the cell, the outside swell and push two cells apart

Answer 12

Associated with xylem transport because minerals are being transported long distance throughout the plant in the xylem. Essential elements: 19 elements that plants need: - 3 that do not come from the soil is the carbon, oxygen, hydrogen - they come from water and CO2 The other 16 come from the soil

Answer 13

- Needed in large increments 1. C, H, O ( needed for everything ) 2. N - need for making proteins, chl, nucleic acids P- need for making nucleic acids, ATP, and phospholipids K- needed for osmotic balance and stomatic functioning S- need for making amino acids Ca- need for making middle lamella Mg-need for making chl Si- need for cell wall strength

Answer 14

- needed in small increments 1. Chlorine, Boron, Molybdenum 2. Iron, Manganese, Sodium 3. Copper, Zinc, Nickle (needed for enzyme cofactors

Answer 15

o Typically, in an ionized form and small. o Roots are responsible for taking up materials in soil  Need transport proteins in the root that will take up one ion (phosphate, nitrate, calcium, etc.) to the xylem o Plants provide minerals to humans o Nitrogen, Potassium, and Phosphorus are limiting resources for plants  The nitrogen in the atmosphere is not accessible by plants because of the triple bonds in nitrogen’s are too strong to break and use (N2)  Haber-Bosch: came up with chemical reaction to convert molecular N2 to organic N2 (ammonia) (N2 ----natural gas---> ammonia) • Have to burn natural gas to convert it to ammonia. CO2 is the biproduct. • Farmers apply extra fertilizer which runs off into the watershed which initiates algal bloom 

Answer 16

o (“phyto” = plant, “remediation”= cleanup of toxic soil in an environment) o Plants cleaning up soil that is toxic to the environment  Hyperaccumulator plants: developed the ability to live in toxic environments and clean them up. • Cadmium (Cd), Lead (Pb), Zinc (Zn), Selenium (Se) toxic in large quantiles; these hyperaccumulator plants will take up these elements and bind them in their cells to neutralize these and suck the bad elements out of the soil.

Answer 17

• Carbohydrate transportation (starch) moves (multidirectional) from “source to sink” or immature leaves to mature leaves (shoot to root) (high carb concentration  low) o “source” is where carbohydrates are made available in excess amounts (high carbohydrate concentration). The main source organs in plants are the mature leaves o Sink organs are where carbohydrates are not made available in high amounts (low carbohydrate concentration). The main sink organs in plants are (main) immature leaves, with the roots, flowers, SAM/RAM  Root function is carbohydrate storage. If herbivore eats leaves off the plant, immature leaves lose their source of carbohydrate and the roots will convert from a sink to a source and begin exporting carbohydrates up to the growing shoot tip. • Phloem tissue contains the phloem parenchyma (storage), phloem fibers (support), sieve tube members (conducting water/minerals long distance) and their companion cells (alive, metabolic functioning for STM) • Phloem moves carbohydrates (sucrose) throughout the cell o Sucrose is an inert sugar (doesn’t react). Sucrose is a disaccharide (small) made up of fructose and glucose together. • The minerals/water can move through the phloem in many directions. The movement is going to be symplastic (inside). Move from source to sink and pusing the minerals up to SAM and down to RAM (positive pressure, low pressure) that results in bulk flow. (“squeezing the end of toothpaste to the top”) o This is not a passive process it requires energy!

Test 3 Flashcards

(41 cards)