Help
Options
Question
Responses to _______ and _______ signals.
click to flip
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't know
Question
Define Behavior
Remaining cards (111)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Bio exam 1, pt.6
Plant Behavior
| Question | Answer |
|---|---|
| Responses to _______ and _______ signals. | Internal and External |
| Define Behavior | any response to stimuli |
| Name two ways plants respond to stimuli during growth and development. | They bend towards light, and they flower at certain times of day and season |
| Signal Transduction Pathways link ______ _______ to _______ | signal reception to response. |
| _______ molecules in plant cells sense stimuli and cause responses | Receptor |
| What are the three stages of Signal Transduction? | reception, transduction, and response |
| Reception: signals are first detected by receptors. What are receptors? | proteins that undergo change in shape in response to a specific stiumli |
| Transduction: transduction of signals involves second messengers and relay of proteins. What are second messengers? | small molecules and ions in the cell that amplify the signal and transfer it from receptor to other proteins that carry out the response. |
| Response: Activation of ______ response | cellular |
| a chemical signal that coordinates different parts of an organism is called a ________. | Hormone |
| Plant hormones were first studied by ______ _______ and his son ______ doing experiments on why plants bend towards light | Charles Darwin, Francis |
| Later scientists found out that plants bend towards light due to a hormone called _____. | auxin |
| One hormone often has _______ effects. | multiple |
| Different __________ or __________ of hormones can have distinct effects | concentrations or combinations |
| Growth hormones generally promote ____ ______, _________, and ________. | cell division, elongation, and expansion |
| What are four major growth hormones of a plant? | Auxins, Cytokinins, Gibberellins, and Ethylene |
| ______ hormones generally slow down growth, promote dormancy, protect plant from danger | Stress |
| What are the two major stress hormones? | Abscisic Acid (ABA), and Brassinosteroids |
| What are the three minor stress hormones? | Salicylic acid (SA), Jasmonic Acid, Nitric Oxide |
| _____ are the most important plant hormone | Auxins |
| There are several different types of Auxins. Name and important one. | indoleacetic acid (IAA) |
| Auxins influences plants in many ways alone or in combination with other _______. | hormones |
| Auxin effects: Establishes the _____-_____ polarity of seed embryos | apical-basal |
| Auxin effects: Induces vascular tissue to _________. | differentiate |
| Auxin effects: Mediates __________ – plant bending towards light | phototropism |
| Auxin effects: Promotes formation of ________ roots | adventitious |
| Auxin effects: Stimulates ____ development | fruit |
| What are some practical uses of Auxins? | Herbicides, Seedless fruit production, Root development on stem, cuttings off the apical meristems of plants promotes bushy growth |
| Cytokinins stimulate ________ | cytokinesis |
| Cytokinins are found in ________ ______ tissues such as root tips, embryos in germinating seeds, and fruits | actively growing |
| Cytokinins work together with auxin to control ___ ______ and _____________. | cell division and differentiation |
| Auxin and cytokinin used together in tissue culture to ____ plants | clone |
| __________ are produced in apical buds, roots, young leaves, and seed embryos. | Gibberellins |
| Gibberellins stimulates ____ _______ and _________. | cell division and elongation |
| Gibberellins interact with light to foster ____ ___________. | seed germination |
| Name 3 things gibberellins enhance. | stem elongation, flowering, and fruit growth |
| Gibberellins retard ____ and ____ aging. | leaf and fruit |
| Ethylene coordinates both ____ _________ and _____ _______. | plant development and stress responses |
| Ethylene influences ____ ________ along with auxin. | cell expansion |
| Ethylene plays a role in defense against ______ stress and ______ attack. | osmotic, pathogen |
| Name 3 things Ethylene is used for | Leaf abscission, Fruit ripening, Triple response of seedlings |
| Abscisic Acid (ABA) slows _____ _____ and promotes ________. | plant growth, dormancy |
| Dormant seeds won’t germinate until ABA is removed by _____, ____, or _____. | water, cold, or light |
| ABA is involved in dormancy of ______ plants in winter | perennial |
| ABA is the primary signal that enables plants to withstand _______. | drought |
| Brassinosteroids induce cell expansion by increasing ______ water uptake | vacuole |
| Brassinosteroids _____ leaf drop | Impede |
| Brassinosteroids Stimulate _____ development | xylem |
| Brassinosteroids Can be applied to crops to help protect plants from ____, ____, high _______, and ________ injury. | heat, cold, high salinity, and herbicide injury |
| In order to survive, plants need to _____ and _______ to a variety of environmental stimuli | sense and respond |
| Photoperiodism | Ability of plants to measure and respond to light amounts and day length |
| Plants have __________ in their cells to detect light, which are different from the light receptors used in photosynthesis | photoreceptors |
| Plants can sense not only the presence of light, but also its _______, ________, and ________. | direction, intensity, and wavelength (color) |
| Photoreceptors have a light-absorbing component and regions that respond to light absorption by switching on ______ ____________ ________. | signal transduction pathways |
| What are two types of plant photoreceptors? | Blue-light receptors, and Phytochrome |
| Blue-light receptors absorb and respond to ____ light | blue |
| Phytochrome are ___ and ___-___ light receptor | red and far-red |
| What are two types of Blue-light Receptors? | Cytochromes and Phototropins |
| Cytochromes help germinating seedlings determine if they have enough _____, and if not, they continue to elongate and push through the soil | light |
| Phototropins are the main ____-_____ sensor involved in phototropism | blue-light |
| Phytochrome can switch back and fourth between two __________, one that reacts to red light, and one that reacts to far-red light. | confirmations |
| Experiments with lettuce seeds showed that germination was controlled by whichever kind of light was the most recent light the seeds were exposed to. If it was red, they ____ germinate. If it was far-red, they ____ germinate | did, didn't |
| Phytochrome also gives the plant information about _____ quality | light |
| Shaded plants receive an increased proportion of ______ light to _____ light | far-red light to red light |
| What are two responses of plants for shade avoidance? | Extension of leaves from shady portions of a tree canopy into the light, Growth that allows plants to avoid being shaded by neighboring plants |
| These responses Occcur by the elongation of branch __________. | internodes |
| Photoperiodism: Plant’s “biological clock” also controlled by _________. It allows plants to sense the day/night cycle. | phytochrome |
| Photoperiodism: Circadian rhythm | plants open and close stomata, fold and unfold leaves, and flower only at certain times of day Plants also keep track of the time of year so that they can go dormant, flower, etc. during the correct seasons |
| Photoperiodism: The relative length of day and night allows the plant to keep track of the ______. | season |
| Photoperiodism: Plants are often classified into ____-___, _____-___, and ___-_______ plants, according to which time of year they flower. | long-day, short-day, and day-neutral |
| Photoperiodism: Despite the name, experiments have shown that the plants are actually measuring the length of the _____. | night |
| _____-___ plants will only flower when the night is longer than some critical length, such as in the late summer, fall, or winter | Short-day |
| ____-___ plants will only flower when the night is shorter than some critical length, such as spring and early summer | Long-day |
| ___-_______ plants flower according to other cues, such as temperature | Day-neutral |
| Gravitropism: ______ are negatively gravitropic – they grow away from gravity | Shoots |
| Gravitropism: _____ are positively gravitropic – they grow towards gravity | Roots |
| Gravitropism: Sensed using starch-heavy plastids known as _______ in cells called ________. | statoliths, statocytes |
| Gravity causes the statoliths to sink to the bottom of the statocytes, which causes changes in _______ ___ messengers | calcium ion |
| Thigmotropism | Plant response to touch |
| Roots that encounter a barrier, such as a rock, will grow ____________ to get around the rock | horizontally |
| Shoots also respond to touch. Name three examples. | Tendrils on vines wind around supporting structures, Wind or rubbing against a plant makes it grow shorter and thicker, Rapid plant movements such as in sensitive plant |
| Stress can be caused by _______ or ______ factors | abiotic or biotic |
| Abiotic: 3 examples | drought, flood, cold |
| Biotic: 2 examples | herbivores, pathogens |
| Plant responses are often mediated by _______. | hormones |
| Flooding: Too much water makes roots unable to obtain sufficient ______ | oxygen |
| Flooding: Ethylene triggers apoptosis in root cortex cells, forming a tissue called ________ | aerenchyma |
| Flooding: The ______-like tubes helps oxygen to get to root cells | snorkel |
| Flooding: Aerenchyma is normally found in plants native to ________ habitats, but can form in other plants in response to flooding | wetland |
| Environmental Stress: _______, ____ ________, ____, and ____ are similar stressors because they all make water less available to plants | Drought, high salinity, heat, and cold |
| What are 4 responses to drought? | Regulating aquaporins, Closing stomata, Growing deeper roots, Slowing shoot growth |
| What are 2 responses to High salinity? | Lowers water potential of soil and reduces water uptake by roots, Plants can produce more solutes in the cells to keep water potential more negative than that of soil |
| What are 2 responses to Heat Stress? | Can denature plant enzymes, Heat-shock proteins produced that protect other proteins from heat stress |
| What are 2 responses to Cold? | Decreases cell membrane fluidity, so plants can alter composition of fatty acids in cell membranes to have more unsaturated ones, Water crystals can rupture plant cells, so some plants can produce antifreeze-like molecules |
| Plants must also respond to biological threats such as _________ and ________. | herbivores and pathogens |
| What are 5 Structural defenses to biological threats? | Thorns and spines, Trichomes, Cuticles, Thick outer bark, and Chemical defenses |
| Defense Against Herbivores: Many plants make toxins that are ____________ or even _______ to herbivores | distasteful, deadly |
| Defense Against Herbivores: Some plants can even “______” the predators of the plant’s herbivores | recruit |
| Defense Against Herbivores: ________ chemical signals released by damaged plants can also warn nearby plants of danger | Airborne |
| Tomato plants release _________ acid when damaged by caterpillars. This signals nearby tomato plants to produce defensive compounds | jasmonic |
| Acacia trees in a park in South Africa killed a herd of antelope by releasing ________ ___, signaling all the acacias in the area to make more toxins in their leaves | ethylene gas |
| Plant pathogens contain ___ genes that encode virulence-enhancing elicitors | Avr |
| Responses to Pathogens: To defend themselves, plants have about __ types of resistance genes (R genes) | 20 |
| Responses to Pathogens: An _ _______ recognizes a corresponding molecule made by the pathogen’s Avr gene | R protein |
| Responses to Pathogens: The R protein then triggers a plant defense like the ____________ ________ and _______ _______ _______ | hypersensitive response and systemic acquired resistance |
| The Hypersensitive Response: Causes ____ _____ at the infection site to deprive the pathogen of food. | cell death |
| The Hypersensitive Response: Strengthens ____ _____ around the infection site to prevent spread of the pathogen to the rest of the plant | cell walls |
| The Hypersensitive Response: Produces ________ at the infection site to kill the pathogen, including hydrolytic enzymes and hydrogen peroxide. | chemicals |
| Systemic Acquired Resistance (SAR) is like a plant _______ ________. | immune system |
| Systemic Acquired Resistance: A localized hypersensitive response results in the production of alarm signals like _______ acid and _________ acid | jasmonic acid and salicylic acid |
| Systemic Acquired Resistance: They travel to the rest of the plant, which makes defensive _______ and ______ like tannins to kill microorganisms | enzymes and toxins |
| SAR is a slower, but ____-________ response | long-lasting |
Created by:
cmccartney2
Popular Biology sets