Exam 2 Flashcards
T/F: Monocots have parallel leaf veins and vascular tissue arranged in a circular pattern.
False
T/F: Wheat and tomatoes are horticultural crops.
False
T/F: Tomatine, a poisonous chemical, is naturally occurring in tomatoes.
True
T/F: The greatest number of stomata are found on the upper side of the leaf blade.
False
T/F: The Christmas legend says the weeds that Pepita placed at the bottom of the nativity scene suddenly transformed int beautiful red flowers and have since been known as “Flowers of the Holy Night.”
True
T/F: Plants in the nightshade family can utilize atmospheric nitrogen to enhance plant growth.
False
T/F: Leaves are sinks for water, but sources for carbohydrates and sugars.
True
T/F: Evergreen plants shed their leaves, just not all at one time like deciduous plants.
True
T/F: Annual plants complete their lifecycle and lifespan in one growing season.
True
T/F: When you eat a potato you are technically eating a tuber; an enlarged underground stem.
True
T/F: Poison ivy is a deciduous perennial plant with compound leaves composed of 3 leaflets.
True
T/F: Monocots have axillary buds at every node.
False
Purpose of sepals
Small, leaf-like pieces attached to the receptacle.
Protects flower bud before it opens.
Neither male nor female.
Role of the apical meristem
In the cell-division zone of plant roots.
Divides cells to increase root length/strength.
What happens when the top eight inches of a tree’s central leader are removed?
Water and nutrients are directed to damaged area to stimulate growth.
New shoots form from upper axillary buds.
Purpose of root hairs
Only portion of the root that absorbs water.
Grow quickly, especially when it rains.
Purpose of root cap
Protects the root tip as it burrows deeper into the soil.
Replaces itself often.
What compound causes the poison ivy skin reaction?
The oil causes an allergic reaction.
The compound is called urushiol.
How can you minimize your chances of developing a rash after poison ivy exposure?
Rinse area that came into contact with oil.
Carefully remove and wash clothing that may have come in contact.
Apply aloe and take an over-the-counter allergy medication, like benadryl.
Two examples of polycarps
Orange trees
Apple trees
Describe angiosperms
Seeds are protected by fruit/ovary.
All angiosperms protect their seeds, however, fruit produced by some plants may be difficult to identify.
Examples of angiosperms
Cherry trees
Peach trees
Sunflowers
Describe gymnosperms
Seeds are not protected by fruit.
Gymnosperms also have flowers, however, they may be difficult to identify.
Examples of gymnosperms
Pine trees
Spruce trees
Why are angiosperms crucial to human survival?
Much of the food humans eat comes from angiosperms.
Soybeans are angiosperms, a large portion of our foods contain soy.
Explain a dioecious plant
Have male OR female reproductive tissues on a single plant.
Pollinator must bring pollen from a male plant to a female plant.
Explain a monoecious plant
Both male and female reproductive tissues are on a single plant.
Examples of monocarps
Carrots
Broccoli
Sunflowers
Explain monocarpic plants
Monocarpic plants flower once in their lifetime, then die.
They can live for long periods of time but viability of offspring is affected by growing conditions (drought/flood).
Explain polycarpic plants
Polycarpic plants flower multiple times in their lifetime.
Considerations when planting gingko trees in a landscape
Female gingko trees produce sticky fruit and emit an odor similar to rancid butter during their reproductive phase.
What is a pollinator?
A living organism (typically an insect) that picks up pollen from a plant and brings it to another one.
What is a pollinizer?
A plant that produces pollen.
How do tree trunks increase in diameter with age?
Cells continue to divide to increase stability and strength.
More branches/leaves=more storage required in stem.
Rings are created by scars that form each time a tree leaves the vegetative phase.
Xylem function
Holds and transports water from the stem to the leaves.
Located on the inner portion of the vascular structure to avoid evaporation.
Phloem function
Holds and transports photosynthetic materials from the leaves to the stem.
Located on the outer portion of the vascular structure to increase sun exposure.
What is guttation?
Comparable to a pressure valve.
Plant releases excess water in droplets on the edges of leaves.
What is cell maturation/differentiation?
Maturation=the production of root hairs.
Differentiation=hairs soak up water and act as an anchor.
What is a polar molecule?
A molecule that contains both negative and positive charges.
What happens when there is an error or problem when a plant is reproducing?
The plant aborts the offspring.
What is the exocarp?
The exterior layer of the ovary.
Fuzzy skin on a peach.
Leathery skin on an orange.
What is the mesocarp?
The middle portion of the ovary.
Yummy fruit on a peach.
White, bitter portion of an orange.
What is the endocarp?
The center of the ovary.
The pit in a peach.
Yummy fruit on an orange.
Explain seed dissemination
Fruit is tasty to encourage animals to eat them.
Stomach acid breaks down seed coat.
Waste is produced away from the mother, giving the offspring a better chance of survival.
Fruit is round so that it can roll.
Some seeds are disseminated through water or wind.
Some seeds explode once maturity is reached (pea pods).
Simple Fruit - Berry
Fleshy, pulpy fruit.
All layers are edible.
Can have 0+ seeds.
Examples of simple berries
Tomatoes
Bananas
Green peppers
Modified Berry - Pepo
Hardened exocarp.
Sometimes have hardened mesocarps.
May need to be cooked before consumption.
Examples of pepos
Watermelons
Pumpkins
Squash
Modified Berry - Drupe
Have a pit (pits are hardened endocarps, NOT seeds).
Examples of drupes
Peaches
Apricots
Plums
Modified Berry - Hesperidium
Anything with an oily, leathery exocarp.
Have natural divided sections.
Citrus fruits.
Examples of hesperidiums
Lemons
Oranges
Limes
Aggregate Fruit
Fruit that forms from a single flower with many pistils.
Examples of aggregate fruits
Raspberries
Blackberries
How to tell the difference between raspberries and blackberries
Blackberries hold onto their receptacle when picked.
Receptacle is ripped out of raspberries when picked.
Multiple Fruit
Many separate flowers fuse to become a single fruit.
The core is the middle portion that holds the flowers together.
Example of multiple fruit
Pineapples
Accessory Fruit
Ovary and other tissues are consumed.
Contain other floral parts in addition to ovaries.
Examples of accessory fruits
Strawberries
Apples
Figs
What is self pollination?
A plant that doesn’t require another plant to pollinate.
What is cross pollination?
Multiple plants are able to pollinate each other.
Pollen from plant A goes to plant B, pollen from plant B goes to plant A.
Function of the seed coat (testa)
Protects seed from environment.
What does the plant embryo do?
Continues the bloodline.
Becomes offspring.
Stages of plant embryonic development
Prembryo stage
Globular stage
Cotelydon stage
Mature stage
Steps of seed germination
Imbibition
Lag phase
Radicle emergence
What happens during seed imbibition?
Dry seed is exposed to moisture.
Typically takes around 24 hours.
What happens during a seeds lag phase?
No weight change for a few days.
Cells are very active due to rehydration in imbibition.
Reactivation and cell division.
What happens during a seeds radicle emergence phase?
Seed coat bursts.
The radicle (root tip) is exposed to absorb water.
The end of germination from a scientific standpoint, not an every day one.
Factors that influence seed germination
Moisture
Temperature (70-75 degrees in most cases)
Oxygen
Light
Seed viability
Soil type
Explain stratification
The moist chilling of a seed.
Lasts for 3ish months.
Must occur for seed to germinate.
People mimic nature to grow plants.
Explain scarification
Breaking a seed coat to allow for plant growth.
Allows moisture into the seed.
Artificial methods of scarification
Sulfuric acid eats away at seed coat.
Sandpaper to scuff portion of seed coat.
Mechanical rollers that crack seed coat.
Explain vivipary
When a seed sprouts while it is still inside the ovary/fruit.
A defect.
Explain adhesion
Water sticks to something other than itself.
Polar molecules magnetize to each other.
Explain cohesion
Water sticks to itself.
The taller the column, the more effective gravity is at pushing out water.
Explain capillarity
Ability of a column to suck up liquid.
Cannot go higher than 40 ft.
Explain diffusion
Molecules are pushed from high concentration areas to low concentration areas.
Why a cup of vinegar can be smelled across the room.
Explain osmosis
Molecules are pushed from high concentration areas to low concentration areas through a membrane.
Membrane acts as a filter.
Explain water movement in the vascular system
Two straws (xylem and phloem) push and pull contents.
Requires minimal energy.
Water continues upward through a membrane, salt can’t.
Water goes up, salt goes down.
Explain the role of stomata in water movement
Water is released to form a suction from the root to the tip.
Water has been in the tip since it was a tiny seedling.
As growth continues, the water chain continues.
Explain transpiration
Plant stomata pushing out water to allow the plant to suck up more.
Called the transpirational pull.
What does softened water do to a plant?
Calcium and magnesium are replaced with sodium.
Salt levels are messed up.
What is photosynthesis?
Turning solar energy into chemical energy
What is respiration?
The consumption of energy created through photosynthesis.
What happens when photosynthesis can’t occur?
Plant starts pulling energy from reserves.
Plant begins to wilt and change color.
Explain the types of waves produced by the sun
Sunlight=free energy.
Plant consumes mainly blue/purple waves during vegetative phase.
Plant consumes mainly red/orange waves during reproductive phase.
Types of chlorophyll
Chlorophyll A
Chlorophyll B
Having multiple types of chlorophyll allows plant to absorb more energy from the sun.
Components of chloroplasts
Chloroplasts are located on the outer edge of cells.
Pancakes (grana) are layered with jelly (stroma) in between.
Functions of stroma (jelly)
Acts as a glue.
Contains RuBisCo.
What does RuBisCo do?
Carries and catches CO2.
Most efficient in a low oxygen environment because oxygen is mistaken for CO2.
Explain the process of photosynthesis
Chlorophyll B grabs hold of energy packets from the sun.
Chlorophyll A grabs hold of the gift from B and spins from excitement so fast that the electron is removed from the molecule.
A is dizzy from losing it’s electron, so it grabs one off of a water molecule.
Water is split into H + O + chemical energy.
Process continues in a cycle each day.
Carbon is connected to become a 6C product.
Chain is split.
3 carbons can turn to glucose (usable energy).
Explain carbon fixation
Converting carbon gas into usable fuel.
Variations in photosynthetic results
More photosynthesis than respiration = growth.
More respiration than photosynthesis = decline.
Photosynthesis = respiration = no change.
Explain CAM plants
Extremely tolerant of environmental changes.
Collect CO2 at night through stomata.
CO2 is converted to malic acid and stored overnight.
Malic acid is deconstructed when the sun comes out to allow for photosynthesis.
Examples of CAM plants
Most cacti varieties
Ochids
Explain C3 plants
Not very efficient.
Majority of plants.
Prefer moderate temp and ample water.
Examples of C3 plants
Lawn grass varieties (turfgrass)
Oats
Explain C4 plants
Tolerate higher temps and less water.
Relatively efficient.
Examples of C4 plants
Crabgrass
Most weeds
Corn
Factors that affect photosynthesis
Water
Temperature
Plant health
