Term
|
Definition
| Eucalyptus scanning electron micrograph. Adapted for xerophytic conditions; thick waxy cuticle prevents water loss. |
|
|
Term
|
Definition
| A xerophytic grass leaf that has adapted to survive in a palce with little water. Surface area has been reduced, as has wind resitance. Water is stored in the leaves and they are swollen as a result. The stoma are small, sunken, and open only at night. The leaves are small and have a waxy outer cuticle to reduce water loss through evaporation. |
|
|
Term
|
Definition
| A xylen vessel that transports water and dissolved minerals over long distances. |
|
|
Term
|
Definition
| Compound Light Microscopy image of phloem, which transports sugars over long distances (photosynthate). |
|
|
Term
|
Definition
| Cotyledon tissue, with protein storage vacuoles. Proteins and lipids are stored in vacuoles within the cotyledons in dicot seeds. |
|
|
Term
|
Definition
|
|
Term
|
Definition
Dicot root cross section.
Labels: 1.Cortex
2. endodermis
3. protoxylem pole
4. metaxylem
5. vascular cyllinder |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Moss; sporophyte and gametophyte generations present. Bryophyte. |
|
|
Term
|
Definition
| Dicot leaf; net variation. |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Monocot; cocount palm tree seedling. |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
1. Lower Epidermis
2. Stoma
3. Spongy Mesophyl
4. Upper epidermis
5. Palisade Mesophyl |
|
|
Term
|
Definition
A. Coleoptile
B. Endosperm |
|
|
Term
|
Definition
1. Vascular Meristem Cells.
2.Pith
3.Explant used in tissue culture
4. Cortex
5. Epidermis |
|
|
Term
| The Arabidopsis microtubule mutant, mor1, has disorganized microtubules. Describe the phenotype of this mutant and what it reveals about the role of microtubules in plant cell expansion. |
|
Definition
| Mor1 mutants are very small as organised microtubulesare important in cell expansion. |
|
|
Term
| What sets the pterophytes apart from the other seedless vascular plants? |
|
Definition
| Megaphylls, large leaves with many branching elements that run together or parallele and are connected by smaller and similar veins. |
|
|
Term
| The scarecrow mutant produces roots that have a layer of cells with both cortex and endodermis characteristics. Why does this occur? |
|
Definition
| Division in the cortex and epidermal cells does not occur; no differentiation can therefore take place. |
|
|
Term
| An Arabidopsis plant produces flowers that have sepals, petals, but not stamens and carpels. According to the ABC model of floral organ identity, which class or classes of ABC genes are mutated in this plant? |
|
Definition
Class C, which is responsible for stamens and carpels.
Class A is responsible for sepals and petals
Class B is responsible for petals and stamens |
|
|
Term
| What floral characteristics are important in plants that use wind as a pollination vector? |
|
Definition
1.large amounts of light and dry pollen
2. extruded stamens or stigma
3. reduced petals |
|
|
Term
| What plant group has double fertilisation? |
|
Definition
|
|
Term
|
Definition
Fern Gametophyte
1. Gametophyte generation
2.rhizome which anchors substrate to soil
4. Antherida, produces sperm (male gametes)
5.Archegonium, produces eggs (female gametes)
6.meristematic region
|
|
|
Term
| What features are present in a pine seed that are not precent in a corn grain? |
|
Definition
| A pine seed has more cotyledons (many are stored in the whorl), a female gametophyte (megagametophyte), and haploid tissue is present. |
|
|
Term
|
Definition
| This is a dicot stem that shows primary and secondary growth. The arrow indicates parenchyma cells, which are responsible for the horizontal/lateral conduction of water and dissoled minerals in woody plants. |
|
|
Term
| How are sugars symplastically loaded into the phloem, and why do they only move in one direction? |
|
Definition
| Sugar moves into the companion cell from mesophyll through the plasmodesmata. There it is converted into raffinose before passing into the sieve element because it is too large to pass back into the pasmodesmata. |
|
|
Term
| What are Pr and Pfr? How is Pfr conerted to Pr? |
|
Definition
| Pfr and Pr are different types of phytochrome, which is a photo receptor in plants. A phytochrome is a protein plus a chromophore. When Pr absorbs red light, it is converted to Pfr. |
|
|
Term
| Explain why water moves apoplastically from roots to leaves on a sunny day. |
|
Definition
| On a sunny day, the stomata are open. Evaporation from leaves is high, therefore transpiration is high. This trasnpiration force is strong enough to move water through the casperian strip and cell walls. |
|
|
Term
| Explain why water moves symplastically from roots to leaves when the sun is down. |
|
Definition
| The stomata are closed. Evaporation through the leaves is low, and therefore transipration force is weak. As the transpiartion force is low, water will move osmotically from cell to cell through the plasmodesmata. |
|
|
Term
| What is the phenotypic response of wild type plants that are shaded by neighbouring plants? |
|
Definition
| Wildtype plants exhibit the shade avoidance response. This includes elongated stems, elongated petioles, and reduced leaf growth. |
|
|
Term
| Describe how sugars are loaded apoplastically, and explain why they move only in one direction. |
|
Definition
| Sucrose moves into the companian cell from teh mesophyll atoplast. It then moves via a transporter protein into the companion cell membrane. It moves into the sieve element from the plasmodesmata. It only moves in one direction because the sugar transporter on which it is loaded only moves in one direction. |
|
|
Term
| What is photomorphogenesis, and how does it benefit the seedling? |
|
Definition
| Photomorphogenesis occurs when an etiolated seedling that has grown in darkness (under soil) moves into the light (aboe soil). It becomes de-etiolated, and chloroplasts form and it becomes green. Its hypocotyl stops growing, and its shoot apical meristem begins leaf production. It benefits the seedling by allowing it to grow up through the soil and get to the light, which it needs for cell respiration. |
|
|
Term
| Contrast what happens to a plant that is capable of accumulating compatible solutes with one that is incapable when there is insufficient water. |
|
Definition
| In a plant that is capable of accumulating solutes, the water potential in the cell will be lower than that in the accompanying soil. This allows the water that is still present in the soil to flow into the plant ia the concentration gradient, and allows the plant to maintain turgor pressure. In a plant that is incapable of accumulating solutes, the water potential in the soil will be higher than that of the cell. Water will therefore flow in the opposite direction, into the soil from the plant. It will be unable to maintain turgor pressure, and it will die. |
|
|
Term
|
Definition
| Opuntia cross-section. Demonstrates xerophytic modification through socculent leaes that are reduced in size and modified as spines. The spines protect from herbivory, but the stems have been modified for photosynthesis and water production and are called cladophylls. |
|
|
Term
|
Definition
Euphorbia spendens/crown of thorns.
Xerophytic modifications: adapts to intermittent dry periods by dropping its leaves and flowers. The spine-covered stems (which protect from herbivory and reduce photosynthesis) exist in a dormant state until wet weather returns. |
|
|
Term
|
Definition
| Desert root systems are often extremely deep and strong in order to reach ground water. Infrequent water encourages deep root growth, while frequent watering encourages surface root growth which is vulnerable to heat and will quickly die. |
|
|
Term
| What are the features of pine needles that make them suited to a cold, xeric environment? |
|
Definition
| Reduced surface area of needle shape, which reduces the aount of water lost. Resin ducts, which store nutrients to deal with extremes of availability. Suken stomatoa, which discourage gass exchange and less water loss, a thick cuticle which protects against temperature extremes, distinctive mesophyll cells with cell wall ingrowths, endodermis surrounding and insulating veins, transfusion tissue, and one or two vascular bundles. |
|
|
Term
|
Definition
Aquatic leaf with aerenchyma.
Aerenchyma are parenchyma with extensive air pockets in teh intercellular spaces. They are an adaptation to living in a wetland. The large intercellular air serve as gas transport, as a reseroir of oxygen, and may give buoyency to the plant. They also limit the cells that require respiration and therfore reduce the need for O2. |
|
|
Term
|
Definition
| Scanning electron micrograph of water lilly. Aerenchyma can be seen in the mesophyll cells noted with an M. The branched sclerids are also present. |
|
|
Term
|
Definition
| A corm is a short, thick underground stem that has been modified to function as a storage tissue. |
|
|
Term
|
Definition
| A tuber is like a corm in that is a thickened stem modified for storage. Unlike a corm, the tuber develops from the swollen tip of the stem and not from the base. |
|
|
Term
|
Definition
| This is an epidermal peel of a transcendentia. The guard cells are clearly visible, as are the stomata. The guard cells contain chloroplasts. |
|
|
Term
| What are the key structural differences between monocot and dicot roots? |
|
Definition
| Monocot roots are adventitious, while dicot roots develop from the radical. The dicot radicle develops into an apical meristem, and roots will develop from their for the rest of the plants life. In contrast, monocot roots are adentitious and emerge from nodes on the plant, often clumped together around the base. |
|
|
Term
|
Definition
| This is a protoplast, which is a cell that has had its cell wall completely removed. They only live for a short period, as they no longer have a cell wall to maintain turgor pressure. They are very delicate and vulnerable to heat and light. |
|
|
Term
|
Definition
| This is a soybean nodule undergoing a bacterial interaction. The plant provides the bacteria with nutrients and a reduced oxygen environment in the nodule. The bacteria performs nitrogen fixation for the plant. |
|
|
Term
|
Definition
| Micchorizal fungi allow root systems to cover much more ground than they would without the fungi and therefore increase nutrient uptake. The fungi also transfers nutrients, especially phosphorous, into the plant. It make also help in co2 adantage. |
|
|
