Bio 2 Exam 3

Eukaryotic organism

Eukaryotic organisms are complex life forms with cells containing a nucleus and membrane-bound organelles.Plants and fungi

Symbiotic relationship

plants and fungi wokring as team

Mycorrihizae

Fungi and plant connections. 90% have this

Algae aquired land adaptations

water conservations, gas?nurtient exchange with air and soil , fetirlizations without water

stomata

used for gas exchange

plant call walls have…

have cellulose, and lignin for cell walls for support

vascular systems in plants

transport water and nutrients

xylem vessels

transport water and minerals from the roots to the stem and leaves

phloem vessels

carry sugars from the leaves to the stem roots and flowers

plants produce what for fertilization

gametes

flagellated sperm cells

algae and plants close to water ofcten have these to swim to fertilize egg cells.

byrphytes

“moss plant” in greek. Also hornwort and liverwort. Flagelated sperm. Non vascular (no xylem or phloem) and dont make seeds. grow low to the grounf and dont have ligmen in their cell walls.

Lycophytes

wolf plants, seedless vascular plants. flagelated sperm. produce spores instead of seeds.

Monilophytes

neckless plants, seedless vascular, grow tall, spores

gymosperms

vascular and produce seeds, seeds not kept in chambers, naked seed,

gymnosperm varieties

conifers (pine trees

Angiosperms

vascular and produce seeds, special chambers for seeds, flowering plants and grasses. majoirty of plant species today.

Plant life cycles

contain diploid and haploid cells. go through distinct stages “alternation of generations”

sporophyte

the diploid stage. this is what we see when we see plant. proudces haploid spores in structures called SPORANGIUM.

spores

spore productions occures via meiosis. spores undergo mitosis to produce and multisellular haploid plant called the GAMETOPHYTE

Gametophyte

produces sperm and egg cells via mitosis

diploid zygote

egg and sperm cells fuse in fertilzation to create this. it growns into a new sporophyte

plant evolution

1. waterconservation

2. gas/nitreint exhange with air and soil

3. support

4. fertilzation without water

seed plants

gymnosperms spread their sperm in pollen granules, produced by pollen cones, which are adapted for air travel. Egg cells stpres in structures called seed cones. Fertilzation of the egg cells by sperm cells will result in seed formation.

gymnosperms

haploid egg cellsa re produced by spores in the SPORANGIA within the seed cone (ovulate cone).

haploid sperm cells

produced by spores in the sporangia within the pollen cone. Unlike seedless plants that release their spores, the egg-making sporangia hold on to their egg cells until they are fertilized and form seeds ●

Seedless plant fertilzation process

seedless plant fertilzation processbegins with pollination as a pollen grain reaches the sporangium of the seed cone ● When the pollen grain reaches the sporangium, the male gametophyte grows a pollen tube ● The pollen tube will provide passage to the female gametophyte ● The female gametophyte also grows to produce an egg cell and a nutrient rich structure ● Fertilization is complete when the sperm cell nucleus reaches the egg cell ● The resulting embryo is encased in the nutrient rich structure, forming a seed ● The seed is the next sporophyte generation (diploid) and can grow into a new plant

Angiosperms

● The life cycle of angiosperms is similar, except aniosperms have their reproductive organs contained in flowers instead of cones ● The stamens are composed of anthers on a filament ○ Antlers produce pollen ● The carpal is composed of the stigma, style, and ovary (female sporangia)

seed fertilzation process angiosperms

Pollen from another plant of the same species is caught by the stigma ● The sperm cells make their way down the style to the ovary, which contains the egg cells ● Just like in gymnosperms fertilization produces seeds

Polllinators

flowers atract animals that facilitate pollen transfer. some plants reuires on species of pollinator.

fruit

Fruit (ripened ovary of a flower containing seeds), is another adaptation of angiosperms to help with seed dispersal

Plants and fungi

Fungi are closely related to plants and animals (in fact, humans are more related to fungi than plants) ● The fungi kingdom contains a vast array of organisms! ○ They acquire nutrients in the same way

Fungi

Fungi are heterotrophs that acquire nutrients by secreting enzymes to digest their food externally and then bringing them into their bodies by absorption ● In many cases, their food is dead animals and plants

Hyphae

The filamentous feeding structures that release digestive enzymes. Specialized hyphae also form the fruiting body which will produce spores ○ In some fungi, the fruiting body is in the form of a mushroom. ● The cells that compose the hyphae are connected by small openings that allow passage of nutrients from cell to cell ● The cells of the hyphae also have cell walls

Mycelium

The network of many branching hyphae of a fungus

Chitin

instead of cellulose (like in plant cell walls), fungi have chitin ○ The exoskeletons of insects and other arthropods also contain chitin

Mycorrhizae

Some fungi mycelium form symbiotic relationships with plant roots. 90% do this

The fungi life cycle

like animals and plants, uses both diploid (2n) and haploid (n) cells ○ However, fungi cells are mostly haploid! ○ In fact, diploid cells only arise briefly in sexual ● In many cases, a species of fungi has two mating types (analogous with female and male in animals) ● Hyphae of opposite sex fungi release attraction chemicals that promote their growth towards each other ● The colored dots represent the nuclei of the different fungal mating types ● The hyphae of opposite mating type fungi will fuse ● Sometimes, though, the nuclei of the two fungal types take a while to fuse (days, weeks, months, years, or even decades!)

heterokaryotic stage (step 1)

• Heterokaryotic means “different chromosomes”, referring to cells that have two different nuclei within them (one from each mating type)

step 2

• When the nuclei from each mating type fuse (step 2), a diploid zygote is formed

• This zygote will quickly begin to undergo meiosis to produce haploid spore-producing structures

• The haploid spores produced from these spore-producing structures are easily spread through air and can grow into new hyphae (mycelium)

germination

The growth of a spore into a hyphae

The mycelium (composed of hyphae)

• will begin the cycle again, searching for a fungus of the opposite mating type

• This competes the sexual reproduction cycle of fungi

most fungi can also reproduce asexually

• This does not require two fungi of opposite mating types and produces genetically identical offspring

• In the asexual reproduction cycle, hyphae (mycelium) of one mating type grows spore producing structures

• These structures release spores that are released and grow new hyphae

• Some fungi only reproduce asexually (ex. Molds and yeasts)

Zygomycetes

•  compose many of the molds, like black bread mold

• They produce a characteristic spherical structures to protect their spores

Glomeromycetes

• are the major fungi involved in mycorrhizae formation with plants

• They enter the root cells of plants to form these connections

Ascomycetes (sac fungi)

produce spores in sac-like structures

basidiomycetes

produce club-like structures that contain spores

Benefits of Fungi

• In addition to their importance form plants (and the ecosystem as a whole), fungi are also extremely important for medicine

  • However, some fungi can cause potentially fatal infections in humans, especially those with weakened immune systems

“goiter belt”

Inorganic fertilizers

• (also called mineral fertilizers) contain inorganic compounds (either naturally occurring or synthetic)

• Inorganic means that the source of the fertilizer is not composed or made from living things

• Inorganic fertilizers come in many brands with a wide variety of nutrients

• Most, however, emphasize N-P-K ratios

Organic fertilizers

• come from biological (living) sources

• This includes compost, a soil-like substance made of decomposed organic matter

• Organic matter is collected in piles which, over time, are decomposed by fungi and bacteria

Top soil,

• A) which is composed of decomposing organic matter

• Mineral and other nutrients can trickle down and become trapped in the next layer (B), which is mostly clay. Roots of plants often extend to B to tap into this reservoir of nutrients

Root hairs

• on roots are responsible for absorbing nutrients from the soil