Chapter 35

What are the locations and functions of meristems?

Meristems - Where growth occurs in plants. Kind of like stem cells in animals.

2 Types of meristems:

apical meristems - growth at the tips of the roots and shoots. When they divided they make the 3 major tissues in plants. Use primary growth.

lateral meristem - Woody plants, with growth that occurs in an increase in diameter. This is involved in secondary growth.

What are the differences between the orgins of primary growth and secondary growth?

Primary growth - The increase in length of the shoot and the root.

Secondary growth - Where the tissues in woody plants get wider stems, branches and roots.

What are the 3 main types of tissues in plants?

Ground tissue - Either protective or photosynthetics

Vascular tissue - consists of two kinds of connecting tissue; Xylem, and phloem.

Dermal tissue - the coverings on the outside of the plant. Have specialized cells called guard cells, that allow gases to get in and out.

What are the three cell types found in ground tissue and their function?

Parenchyma - the most common type of plant cell, and is the photosynthetic tissue

Collenchyma - structural, supportive tissue in the living parts

Sclerenchyma - structural supportive tissue in the dead parts of the plants, like roots, which help move nutrients.

What is the difference between the xylem and phloem structures and their functions?

Xylem - conducts water and dissolved minerals.

Phloem - conducts a solution of carbohydrates—mainly sucrose-used by plants for food.

What are the major structures and functions of the four parts of a root plant?

root cap - protects the apical meristem from corrosion from the soil

zone of cell division - area of growth produced by the meristem

zone of elongation - The area where the cells grow

zone of maturation - where the cells fully mature and become real cells.

What is the function of root hairs?

Root hairs - They greatly increase the surface area and therefore the absorptive capacity of the roor.

• Symbiotic bacteria that fix atmopheric nitrogen into a form usable by legumes enter the plant via root hairs.

What are the functions of modified roots?

Aerial roots - growth unconnected to the ground, and have roots that extend into the air (photosynthetic).

Pneumatophores - plants that grow in swaps and other wet places, have underwater roots, that extend several centimeters above water.

Food storage roots - Where the xylem of branch roots of sweet potatoes and similar plants produced extra parenchyma cells that store large numbers of carbohydrates. They have multiple strings of secondary growth.

Water storage roots - roots that are able to store water weighing 50 kg or more.

What are the contributions of an axillary bud to plant form?

axillary buds - form new stems as they grow,

What are the differences between cross sections of a moncot stem and a eudicot stem?

moncot stem - grasses, corn wheat, etc. Hae vascular bundes spread out

eudicot stem - woody plants, vascular bundles are arrages in circles by the outer layer of the stem. This allows for secondary growth.

How do leaf structures affect gas exchange and water loss?

Guard cells - gaurd if the pores are open of closed, inorder to reduce water loss.

• They help make sure that gas exchange is consistent enough for plant survival and reduces water loss.

Chapter 36

What are the three water transport rount through plants? How do they differ from one another?

apoplast route - moves around the cells walls.

symplast route - moving through the pores in the walls

transmembrane route - the water moves through the cell membrane. Can be regulated

• Transmembrane filters better than the other routes.

How does water potential effect water transport in the xylem?

Root pressure - occurs at night, and is caused by the continued accumulation of ions in the roots at times when transpiration from the leaves is very low, which make it have to balence out the concentration, forcing its way in.

• This effects water transport in the xylem by affecting the osomolarity in the xlyem.

How does the properties of water enhance transpiration?

• Water only moves through the plant if the water potential of the soil is greater than in the root.

  • too much fertilizer or drought conditions lower the water potential of the soil, which limits water flow.

What happens to the state of a stomata under different environmental conditions?

Stomata open - vapor is lost to the external environment, increasing the rate of transportation. the plant opens the pores when it wants water, and inorder to do this tugar in guards cells is made by the active uptake of potassium chloride and malate. inflating the guard cells.

• stomata is controled by the plant based on the amount of water is present, effecting tugor pressure

• plants must maintain a balance between gas exchange and water loos.

Stomata close - caused by water stress, high temps, and high carbon dioxide concentration.

How do mechanisms regulating stomatal opening respond to conditions external and internal to plants?

• To cope with various environmental stimuli, plants can optimize the opening and closing of stomata to balance CO 2 uptake for photosynthesis and water loss from leaves. Guard cells perceive and integrate various signals to adjust stomatal pores through turgor pressure regulation.

How do plants adapt to survive conditions of drought, flood, and high salinity?

arrenchya - fills parts of the pant with air, whitch helps photosynthesis to continue.

• Plant responses to stresses like heat, high salinity and drought involve a rapid, reversible process that modifies proteins

What is the pressure-flow hypothesis?

pressure-flow hypthesis - explains the movement of sap through the phloem of plants.

• the presents in the plants body of sources, and sinks.

Sink - We are extracting sugars, into the tissues to help with growth. This reduces the pressure.

Source - Moving sugar into the phloem, inorder to grab more water from the xylem, increasing the pressure.

• Moves from high to low concentration.

Chapter 37

How does soil interact with negatively and positively charged ions?

Negatively - The smallest soil particles have a ne charged, to be able to hold a postively charged particle

Positively -

• The plant does a positive exchange to beable to grab the minerals and elements they need to live.

What is the difference between macronutrients and micronutrients?

Macronutrients - The things the plant needs in large amounts, example; carbon, O2, hydrogen, and nitrogen.

Micronutrients - more specific for why they are needed, and are needed in small amounts, example; chlorine, Iron, Boron, etc.

What is the goal of food fortification research?

Food fortification - is an active area of resarch focused on ways to increase the uptake and storage of minerals in plants grown for human consumption.

• The goal is to be able to add vitamines to the foods.

What is the significance of nitrogen-fixing bacteria for plant nutrition?

• Plants need nitrogen for ammonia, to build amino acids, and have a limited supply because it is usually only found as nitrogen gas.

• Since plants lack the pathways needed, they team up with some bacteria that help form root nodules, are able to help in the uptake of nitrogen in the soil and environment around it.

How does mycorrhizal fungu benefit plants?

Mycorrhizal fungi - help enhance phosphate transfer to the plant, which also allows the plant to share some of its sugar with the fungi.

What are the benefits gained by carnivorous plants when they capture insects?

By captureing and digesting smal animals, the plants obtain the nitrogen supplies they lack, which helps them grow in tough environments. that lack nitrogen in their soil.

What are the predicted effects of increased atmospheric carbon dioxide on the rate of photosynthesis in C3 plants?

• if we increase CO2 it will increase photosynthesis, not really true because there are other things we may runout of.

• We need to still maintain the other compounds to maximize the growth.

• DOES NOT help increase photosynthesis very much.

what is phytoremediation?

Phytoremediation - The process that uses plants to remove contamination from soil or water.

• helps trap the toxins, inorder for them be removed.

• We use this to help clean up toxic places.

Chapter 38

What are the steps taken by a fungus to invade a plant leaf?

1. Windblown spores land on leaves, a germ tube appears from the spore, and the host recognition is necessary for gemination.

2. The spore germinates and formed an adhesion pad, allowing it to stick to the leaf.

3. hyphae grow through cell walls and press against the cell membrane

4. 4. hyphae differentiate into stuctures called haustoria, which expand and surround the cell membrane, and start nutrient transfer.

What is the role of secondary metablites in plant defense?

Secondary metabollte - A molecule not directly involved in growth, development or reproduction of an organism; in plants these molecules, can discourage herbivores.

• These help overstimulate their attacker, which allows for a good defense.

What is allelopathy?

Allelopathy - the release of a substance from the roots of one plant that blocks the germination of nearby seeds or inhibits the growth of a neighboring plant.

What are the benefits acacia trees reveive from ants that live in them?

• The ants in the acacia tress provide small armies to protect the trees from herbivores.

• They attack other insects, small mammals, and epiphytic plants that could harm the trees.

• The Acacia trees sometimes provide the ants with sugar in their flowers.

How do some plants use parasitoid wasps to destroy caterpillars?

• since caterpillars feed on leaves, plants use wasps to help get rid of them

• Other plants release a compound in result to the bite marks from the caterpillar, which signals a female wasp, which then lays its eggs in the body of a caterpillar, and when the eggs hatch, it kills the caterpillar.

What is the sequence of events that leads to the production of a wound response?

Wound response - a signaling pathway initiated by lead damage, whihc leads to the production of proteinase inhibitors that give these herbivores eating the plant indigestion.

Steps of the production of a wound response:

1. Wounded leaves produce systemin from a larger precursor protein

2. The systemin moves through the space between the cell wall, of the wounded tissue and into the phloem, which moves throughout the plants through the phloem.

3. Cells with a systemin receptor bind to the systemin, which leads to the production of Jasmonic acids.

4. The JA activates the transcription of the defense genes, which includes the production of a proteinase inhibitor.

What is systemic acquired resistance?

Systemic acquired resistance - In plants, a longer-term response to a pathogen or pest attack that last days to weeks, which allow the plant to respond quicker to later attacks.

Chapter 39

What are the growth responses influenced by phytochrome?

1. growth patterns.

   • phototropism - A plant pigment that is associated with the absorption of light, photoreceptor for red to far-red light.

2. molecules, phytochromes triggers germination and growth, other ways that plants responds to light,

• plants can pervieve and respond to their stimuli.

What is phototropism?

Phototropisms - directional growth responses to light

What are the structires in cells that perceive gravity?

gravitropism - driectional response, to gravity,

• stems grow up

• roots grow down.

They perceive gravity in structures call amyloplats, these move based on gravity, wheather tiped or moved upside down.

What is the differences between thigmotropism and thigmonastic responses?

Thigmotropism - unequal growth in some structures that comes about as a result of physical contact with an object.

Thigmonastic responses - are similar to thigmotropism, but the direction of the growth response is the same regardless of the direction of the stimulus.

Why is seed dormacy an important evolutionary innovation?

Seed dormacy - The evolutionary innovation of the seed plants is the dormant seed that allows plant offspring towait until conditions for germination are optimal.

What are the types of biological molecules that are directly affected by low and high temps?

high temps - In plants, they produce heat shock proteins, which can stabilize proteins so that they don’t unfold or misfold during denaturating.

• plants protiens unfold

Low temps - Plats proteins, become stiff.

What are the properties of hormones?

hormone in plants - stimulate growth in a plant,

Ethylene - is a gasous hormone that can cause other compound that lead to ripening.

Abscisic acid - lead to the fruit or leaves dropping of the plants.

What is the differences between auxins and cytokinins?

Auxins - produced by the tip of the stem stopping lateral axillary buds from growing.

Cytokinins - Stimulate lateral bud growth.

Chapter 40

What is the general life cycle of a flowering plant?

alternation of generations:

• sporophyte (2n) producing haploid (x) spores by meiosis

• Gametophyte (n) genertion producing a diploid (2x) embryo by fertilization.

  • Have both male and female Gametophytes.

What are the four genetically regulated flowering pathways?

1. Light - It is the uninteruppted darkness that causes it to flower. (based on the darkness not the light)

   • long day plants - flower when the day is long

   • short day plants - flower when the day is shorter.

2. temperature

3. hormone

4. gene dependent.

What is floral determination?

Floral determination - the point at which shoots (stems) become committed to making flowers.

• There is a point where a stem is developed enough where it can reproduce.

What is the relationship between floral meristem identity genes and organ identity genes?

The ABC model:

1. Class A genes alone specify the sepals

2. Class A and Class B together specify the petals

3. Class B and class C together specifiy the stamens

4. Class C genes alone make the carpels.

What are the parts of a typical angiosperm flower?

Sepals - are before the flower opens, the cover of the bud.

Petal - are the outer part of the flower.

Stamen - Male part of the flower, consists of anther, and filament.

Carpel - Female part of the flower, consists of stogma, style, ovary, and Ovule.

• pistils - make up the carpel, one or more of these make up the individual segments and contain the seeds.

• Ovules - develop into seeds.

What is the difference between microgametophytes and megagametophytes?

Microgametophytes

megagametophytes

What conditions of self-pllination are favored?

1. Outcrossing - breeding between two different individuals.

1. separte pistals and

2. genetic incompatibalily

What are the products of double fertilization?

Double fertilization - producesOne of the sperm cells fertilizes the egg cell, forming a zygote, the other sperm cell fuses with the two polar nuclei located at the center of the embryo scac, making the food source for the egg.

What are the events that occur during seed germination?

germination - a process that is the emergence of the radicle first root through the seed coat.

Events that occur during seed germination:

1. water getting to the seed allows for the radicle to emerge.

2. Stem emerges from the soil, and become photosynthetic

3. Starts to photosynthize on its own.

What is apomixis?

Apomixis - where plants develop seeds without fertilization.

• gain the advantage of seed dispersal,

What are some examples of plant parts involved in vegetative reproduction?

Vegetative reproduction - non reproduction parts of the plants.

• Any part of a plant that contains seeds, is a fruit.

Runners or stolons - Long, slender stems that grow along the surface of the soil.

Rhizomes - Stems running underground that give rise to clones for the new plants.

suckers - roots of some plants that give rise to new plants. seeds are propagated by the suckers that develop form buds on underground stems.

adventitous plantlets - Are on the leaves, fall off and make their own root and shoot system, which grow.

What are perennial plants?

perennial plants - May be herbaceous, live for years, and continue to growth for years.

What are annual plants?

annual plants - have their whole lifecycle for one year.

What does the life cycle of a biennial plant look like?

Biennial plants - take 2 years for their full life cycle.