BIOL 198 KSU Module 6: Plant Biology

How are Lichens formed?

Lichens form from a mutual relation of Algae and Fungus

What is a lichen good for?

Early colonizers of bore rock, organisms eat them, they provide cover for small organisms, and weavers can use them for dye

Where is Red Algae common?

Red algae is more common in water. Has been found 260m deep

Where is Green Algae common?

Green algae is more common on land, and shares plant characteristics

Why are algae important to humans?

Food, additives, medicine

What biochemical and structural evidence supports that plants and green algae are thought to have common ancestors?

Both used chlorophyll A&B plus carotene in a particular ratio, they share the trait of cellulose-rich cell walls and strong molecular support for their close relationship

What does the life cycle of Chara have that is similar to plants?

It has a haploid and diploid stage, and follows a life cycle

What are the main challenges that needed to be overcome in order for plants to live on land?

Desiccation
Gravity
Mating
Air doesn't filter harmful UV rays

What features of the terrestrial environment made it advantageous for plants to invade land?

Sunlight is abundant, less filter for chlorophyll
CO2 is more readily available
No predators early on

What are the adaptations plants have developed to live today?

Defenses
Live close to water, to combat dryness
Colonized communities with high humidity

All algae are __________

Eukaryotes

What are the 4 major types of plants?

Bryophytes, Seedless Vascular Plants, Gymnosperms, and Angiosperms

In the main dispersal phase, bryophytes' spores are in what state? Haploid or Diploid

Haploid spore

What is the dominant stage (the one we see) of Bryophytes?

Gametophyte, haploid

Since bryophytes have swimming sperm, what is a requirement for reproduction?

They must be in water

Bryophytes can't grow really tall because...

They lack vascular tissue which contains lignin

The sporophyte generation in Bryophytes is ______________ on the gametophyte

Dependent

When a generation is dependent on another, what does this mean?

Each one has energy and certain nutrients that the other generation needs in order to complete it's process for the next generation. This is shown through the creation, breakdown, and reproduction of the transport tissue, seeds, flowers, and fruits.

In the main dispersal stage of seedless vascular plants, is the spore haploid or diploid?

Haploid

What is the dominant stage in seedless vascular plants?

Sporophyte, Diploid

Since seedless vascular plants have swimming sperm, what is a requirement for reproduction?

They must be in water

Why can seedless vascular plants grow tall, unlike bryophytes?

They have vascular tissue which gives them structure

In Gymnosperms, is the main dispersal stage haploid or diploid?

Diploid

What is the dominant stage in Gymnosperms?

Sporophyte, Diploid

What type of spore does the sperm come from and what type of spore does the egg come from in Gymnosperms?

Microspore = sperm
Megasporte = egg

Gymnosperms have different gametophytes. What does that mean?

They are heterosporous which means they have megaspores and microspores. This creates the male and female reproductive parts of the gymnosperm.

In the main dispersal stage of Angiosperms, are they haploid or diploid?

Diploid

What is the dominant stage sporophyte or gametophyte in Angiosperms?

Sporophyte, Diploid

What type of spore does the sperm come from and what type of spore does the egg come from? (Angiosperms)

Microspore = sperm
Megaspore = egg

Do angiosperms have swimming sperm, and require water for fertilization?

No

What role does fruit serve

seed dispersal; animals eat the fruit and then defecate the seeds spreading them around

What do gametophytes produce? Through what process

Gametes, mitosis

When a male and female gamete meet to form a zygote, this is called....

fertilization

Are sporophytes haploid or diploid?

Diploid

What reproductive cells do sporophytes produce? Haploid or Diploid, and through what division process?

Haploid spores through meiosis

Are gametophytes haploid or diploid?

Haploid

Define vegetative reproduction:

A form of vegetative reproduction when a new plant grows from fragments/cuttings of a parent plant done through mitosis. Meiosis is used to create haploid cells that have half of the genetic information of the parent plant (one of every chromosome)

What is a meristem?

The regions of the plant where continuous cell division and growth occurs

Apical meristems are...

located at the tips of stems and roots which cause length growth

Lateral meristems...

facilitate growth in thickness or girth in a maturing plant

Dermal tissue

covers and protects the plant

Vascular tissue

made up of the phloem and xylem; xylem transports the water various parts of the plants, and they phloem transports nutrients to different parts of the plant

Ground tissue

serves as a site for photosynthesis

Anther in a flower

holds pollen, the male reproductive cell

Ovary

Female reproductive part of a flower

Ovule

Reproductive cell found in the ovary

Is pollen a sporophyte or gametophyte?

Gametophyte

Vascular bundle

A structure formed by xylem and phloem in the stem

Pith

the ground tissue towards the interior of the vascular tissue in a stem or root

Primary vs Secondary Growth

Primary = length
Secondary = girth

What mode of pollination are modified grasses most likely to use?

Wind

Which agent of pollination is a showy flower, like a petunia going to use

Insects; they like colors

Tap Root System

Has a main root that grows down vertically and from which many smaller lateral roots arise. Penetrates deep into the soil

Fibrous root system

A root system that is located closer to the soil surface, and dorms a dense network of roots that also helps prevent soil erosion

Pollination

The transfer of pollen to the stigma of a flower

Fertilization

The union of the haploid gametes to produce a diploid zygote

What is a seed?

The mature ovule plus stored food

What is a fruit?

A mature plant ovary, containing seed

What is seed germination?

The beginning of growth by a dormant seed; this is triggered by different environmental conditions such as soil temp, soil moisture, oxygen levels, and the amount of daylight; usually begins with imbibition

What is imbibition?

the uptake of water into the seed

Monocots:

Has flower parts in multiples of 3, fibrous roots, random stem vascular bundles, and parallel leaf vains

Eudicots:

Has flower parts in multiples of 4 or 5, tap roots, circular stem vascular bundles, and net-shaped leaf veins

Define tropism:

The response of a plant toward or away from a stimulus

What is phototropism?

A directional response that allows plants to grow towards (positive), or even away from light (negative).

What is gravitropism?

A growth response to gravity negative is up, positive is down.

Role of cohesion:

Water molecules sticking together allows the water column within the xylem to move as a unit. Works because when water is evaporated, it pulls on the water column

Role of adhesion:

Water molecules sticking to something else- helps prevent water from sliding back down the xylem

Root cap

Protects the tip of the root - gets replaced rapidly

Zone of cell division

zone by the root tip. Made of actively dividing cells

What is the xylem?

The tissue that water and minerals move through

What is the phloem?

The tissue where glucose and sugars move through

Endodermis

Layer of cells that separated the vascular tissue from the ground tissue in the outer portion of the root

Root hairs

Extensions of the roots, meant to add surface area to the root system.

Route of movement of water from soil to leaves:

Enters via 2 pathways: through the root hairs; moving in between the epidermal cells. Once in the root it must pass through several layers of tissue (epidermis, cortex, endodermis) to the xylem, through the spongy mesophyll, and then out through stomata.

Upper epidermis:

Upper tough outer layer of the leaf that helps protect, and support

Leaf vein:

Contains the leaf's xylem, and phloem

Stomata:

Openings in the leaf through which the exchange of gases takes place

Palisade mesophyll

Densely packed photosynthetic cells in the upper part of the leaf

Spongy mesophyll

The loosely packed photosyntheic cells in the upper part of the leaf

Plant adaptations for differing water levels:

Waxy cuticles, leaf hairs, and alternate carbon fixation paths

C3 pathway:

Cost: Photorespiration
Benefit: carbon fixation without using ATP
Habitat: cool and moist
No separation of light-dependent reactions and carbon fixation

C4 Pathway:

Cost: costs ATP to fix carbon twice
Benefits: reduced photorespiration and carbon fixation in high temperatures
Habitat: hot
Spatial separation of light-dependent reactions and carbon fixation

CAM Pathway:

Cost: reduced amount of fixed carbon
Benefits: reduced photorespiration and water loss
Habitat: hot and dry
Temporal separation of light-dependent reactions and carbon fixation

Limiting factors on food production

Amount of land available, amount of arable land, which trophic level providing for, adequate rain and nutrients

Biological factors that limit the conversion of solar energy into food

Wavelengths of light, energy needed to grow/reproduce,

Greenhouse effect

Greenhouse gasses such as CO2 and methane trap heat that would have otherwise radiated back

Mycorrhiza

A type of fungus that form symbiotic interactions with plant roots by secreting enzymes that make minerals water-soluble and absorb those minerals from the soil to transport them to the host plant. The host plant provides food.

Symbiotic nitrogen fixation

A mutually beneficial relationship between a plant (which provides food) and a nitrogen fixing organism

What is the function of the casparian strip?

directs water movement into the vascular tissue

What is the stigma of a flower?

where pollen grains land the and the sperm from the pollen starts to penetrate the carpal

What is style?

the long stalk supporting the stigma

What is the ovary?

where the eggs develop and are fertilized

What is the sepal?

small leaves under the flower

What is the Petal

It is a bright colored part of the flower that's odor and color attracts pollinators.

What is the anther?

where the male gametophyte--pollen--is produced

What is the filament?

a supporting structure for the anther

What is the ovule of a flower?

structure that develops into a seed when fertilized

What is the receptacle?

The part of the plant that connects the flower to the pedicel and supports the entire flower.

What is the shoot system?

consists of two portions: the vegetative (non-reproductive) parts of the plant, such as the leaves and the stems, and the reproductive parts of the plant, which include flowers and fruits; generally grows above the ground and captures light for photosynthesis

What is the root system?

supports the plants and absorbs water and minerals, is usually underground.