Biodiversity Test 4

Alternation of Generations-

•  a life cycle held not only by green plants, but also other algae. Two different multi-cellular life stages. 

Sporophyte-

• produces spores. 

  • Spores develop into gametophyte

Gameotophyte

• produces gametes

  • Gametes (male and female) fuse and develop into sporophyte

• Earliest plant fossils- 400 mya were

Spores

• Terrestrial Plants- Green plants- and Charophycean  is significant because

• Algae are more similar to each other than either is to any other group of algae morpholgically, phsicologically, Genetically

Morphologically

• structurally more similar

Physiologically

• how metabolic processes are carried out

Genetically

• DNA more similar

We DONT say that green plants came from charophycean so we DO say

• Green plants and charophycean algae share a common ancestor

• Charophycean algae may serve as the model for the ancestor of green plants 

• Two hypotheses for how the aquatic ancestor of GP moved onto land….

• 1) Seasonally Dry Pond Bed Hypothesis

  • When the pond dries up, the ancestor is left stranded on dry land for 2-6 weeks.

  • 2) Splash Hypothesis- 

    • As the tide goes out, the ancestor is stranded on dry land, until the tide comes back in (12 hours)

    • Charophycean algae and green plants both make a protein, sporopollenin that protects against dessication. 

Why would the move onto land be favored by selection?

Easy access to: 4 things

• 1 Sunlight-  not filtered out by water

• 2 Nutrients- soil is a bed of nutrients.

• 3 C02- dried access to C02 gas

• 4 Briefly- few or no herbivores

Adaptations unique to Green Plants- 3 things

• 1. Waxy cuticles- prevents water loss from leaves.

• 2. Stomata- pores for gas exchange to take place C02 in ; O2 out (?) ; H20 out

• 3. Roots and Shoots- regions of rapid cell division to increase length of branches and roots to compete for sunlight and nutrients. 

Four Major plant Groups- 3 only

Bryophyte, Monilophytes, Spermatopsida

Bryophytes

• The non-vascular plants

  • Non-vascular = no system devoted to moving water and nutrients around the plant. Instead, water and nutrients move via diffusion cell to cell.

  • No true leaves (photosynthetic organisms) or roots

  • Limited in height- moss

  • Gametophyte is dominant

    • Sporophyte grows off the gameophyte like a branch.

    • Sporophyte “dependent” on gametophyte for water and nutrients.

  • Water dependent reproduction- sperm must swim to egg.

  • Limited to damp environments. 

Monilophytes

• (ferns)- Seedless Vascular Plants.

  • Vascular system present.

  • True leaves and True Roots

  • Grow tall

  • Sporophyte Dominant

  • Gameophyte Independent of Sporophyte

    • Gametophyte is a separate plant. 

  • Water-dependent reproduction. Sperm must swim to egg.

  • Limited to damp environments 

Spermatopsida

• Seed-bearing vascular plants

  • Vascular system

  • True leaves and roots

  • Can get big!

  • Sporophyte Dorminant.

    • Gametophytes dependent on Sporophyte Gametophyte are microscopic.

  • Male Gametophyte = inside the pollen grain. **Pollen doesn’t require water for dispersal. No longer dependent on water reproduction. 

  • Seed- a sporophyte embryo packed with a nutrient supply.

Gymnosperms

• (means naked seed) pine cones- Cone-bearing

  • Female cone- large, brown

    • Each blade contains 2 female gametophytes

  • Male cone- small, yellow

    • Each pollen grain is 1 male gametophyte.

  • Pollination is dependant on wind

Angiosperm

•  (vessel, fruit)  flower bearing plants.

  • Both Male and female Gameophytes are in the flower.

  • Pollination depends heavily on animals. 

    • Insects, birds, bats.

  • **Fruit– seed dispersal mechanism. Derived from the ovary of the flower. 

Structure of the Fungi (name them)

• The actual body of a fungus is an interwoven mat of filaments

• *Individual filaments- hyphae

• *Interwoven mat- mycelium

• The mycelium is always embedded in a matrix- a rotten log, the ground, ect

• *Hyphae grows up above ground to form a fruiting body- which produces spores 

• Fungi are haploid

• Cells are coenocytic, The cell walls are incomplete and the cytoplasms of all the cells run together. 

Four Phyla- 

Chytridimomycota, Zygomycota, Ascomycota, Basidiomycota

Chytridimomycota (Chytrids) Charatristics

• Fully aquatic

• Maybe most similar to the aquatic ancestor of fungi.

• Important parasites of fish and amphibians

• -> Indicator species-

  • Decline of an ecosystem often begins with chytrid infection in fish and amphibians.

Zygomycota characteristics

• Includes bread molds

Ascomycota characteristics

• Associated with White Nose Syndrome in bats.

• Toxic- morral. People still eat them though

Basidiomycota characteristics

• The mushroom we eat. 

• “Gills” - carry spore- producing structures.

Mold

Fungus that’s somewhere you don't want it to be. 

Stachybotrys

•  “toxic black mold”

  • Usually brought into the house via flooding

  • At this time, there’s no link between stachybotrys and the neurological symptoms associated with it

Yeast

Single-celled fungi- No mycelium/ hyphae

Saccharomyces

• produces ethanol and C02 as byproducts of fermentation.

  • Co2- Makes bread rise

  • Ethanol- alcoholic beverage

Lichen

 a symbiotic relationship between a fungus and photosynthetic partner (bacteria or algae)

• Obligate mutualist-cant exist independently, Together, a single species- 25,000

Mycorrhizae

Symbiotic relationship between fungus and plants (roots)

• Not obligate!

• 95% of all vascular plants have mycorrhizae

• The earliest fossils of plant roots show mycorrhizae.

Our interactions with Fungi

Ringworm, Athlete’s foot/ Spring itch, Thrush (infants), Yeast Infection,  other fungal infections

Ringworm

•  children inadvertently handle cat poop. 

 Athlete's foot/ Spring Itch

• associated with being hot and sweaty

 Thrush (infants)-

• your body’s symbiotic candida gets out of control due to an underdeveloped immune system.

Yeast Infection-

•  Candida out of control in your reproductive tract.

Other fungal infections

• really only appear in people with compromised immune systems.

  • HIV

  • Immune diseases like MS

Chitin

 is the primary constituent of the cell wall. (beetle)

*Dna sequence date shows fungi are more closely related to animals than plants

ANIMALS- How do we define them? 3 things

• 1) Chemo-hetro-trophic

  • Energy derived from eating organic mols

  • Carbon 

• 2) Motile- can move self around

• 3) Multicellular

What was the ancestor of animals like?

-Maybe similar to a Choanoflagellate.

- *Can live independently or in a colony.

-May serve as the model for the bridge between single-celled and multi-celled organism.

(know image) 

Name Level 1- classification of animals

• Presence of Tissue

• *Tissue - a group of cells that perform a common task that benefits the entire organism. Such that no ind cell has to perform all the task required for survivals (specilzation of labor)

• No tissue- sponge

• Yes tissue- everything else

Name level 2- classification of animals

• symmetry- how many planes can divide an object into mirror image halves

• Radical- any plane through the midpoint divides an organism into mirror image halves. 

• Crindarians- jellyfish and Corals

• Bilateral- only one place.

  • Everything else (above the level)

Jellyfish Polyp reproduction

• Polyp

• Adult

• Reproduces a sexually. Budding or prodcuce Medusa

How does this reproduce?

• Medusa

• Juvenile

• Reproduces sexually

• Produces planilae

How does this reproduce

• Planta

• Dispersive

• Sink to the ocean floor and become a polyp.

• **Most jellyfish complete the entire life cycle.

• In some species, the polyp is obsolete and they only exist as medusa.

• In some species, the medusa is obsolete, and they only exist and polyps.

What is level 3 for classification of animals?

 Patterns of Embryonic Development

• At the eight-cell stage- 

• Protostome- The 8 cells are determinant; they’re stem cells

• Indeterminant- they’re NOT stem cells

• Deuterostome- the 8 cells are indeterminate- They’re NOT stem cells. Each cell could develop into a complete organisms.

• *identical twins

At the 100-cell stage-

 hollow ball of cells

The digestive system starts to form.

• The blastophore will either become the mouth or an anus.

  • Protostome- blastopore becomes the mouth.

  • Deuterostome- blastopore- becomes anus.

  • * Deutersomes= Echinoderms (star fish) and Chorates

  • *Protosomes= everything else.

What is level 4 for the classification of animals?

Growth After Hatching

What is an adder?

•  add new cells at a constant rate.

  • Flatworms- ex tapeworms

  • Annelis- ex Earthworms and leeches

  • mollusks - ex Octopods, bivalves, gastropods (snails)

What is a molter?

• have a hard exoskeleton

  • Molt the old exoskeleton 

  • Period of Rapid Growth

  • Secret a new exoskeleton

    • Roundworms

    • Insects- 3 body parts / 6 legs

    • Spiders- 2 body pats/ 8 legs

    • Crustaceans- ex. lobster.

The Four Characteristics of the Chordates:

• Dorsal, hollow nerve chord.

• Notochord- supports the nerve chord.

• Pharyngeal Slits– gills–  for us, present in embryonic development.

• Post-anal tail- notochord extends beyond the pelvis. 

  • For use, the coccyx- used as a muscle attachment site.

Ancestor of Chordates?

• Maybe something like a Tunicate. 

  • Has the 4 characters of the Chordates in the larval stage. 

  •  A perfect combination of Invertebrate and Chordate Characters.

  • May serve as the model for what the ancestor of chordates was like.

Classification of the Chordates- name all levels

Level 1: Brain

Level 2: Cranium and Cephalization 

Level 3:Vertebral Column

Level 4: A lot of things happen at once

Level 5: Lungs

Level 6: Lobe fin

Level 7: Legs

Level 8: Amniotic Egg

Level 9: Milk

Level 1 for Chordates

• Brain

  • Ex Lancelet- a slightly enlarged region on the anterior end of the nerves chord. 

  • This may serve as the model for, the evolution of the brain 

Level 2 for chordates

• Cranium and Cephalization 

  • Cranium- protection of brain

  • Cephalization- the aggregation of the major sense organs on the anterior end (head)

  • Ex. Hagfish- have a loosely woven cartilaginous basket that surrounds the brain

  • This may serve as a model for the evolution of the cranium.

Level 3 for chordates

• Vertebral Colum- 

  • Notochord surrounds nerve chord

  • Ex. Lamprey- notochord is a stiff cartilaginous rod, and may serve as the model for the evolution of the vertebral column. 

Level 4 for chordates

•  A lot of things happen at once:

  • Jaws- more powerful opening/closing

  • Jointed Vertebral Column- more powerful tail

  • Paired pectoral and pelvic fins- increased maneuverability 

  • ** Active predation/ evasion- ex sharks and Rays

Level 5 for chordates

•  Lungs

  • Ex. Bony Fish- 

  • Bony skeleton- preserves well in fossil record. 

  • Swim bladder- 

    • Originally for gas exchange

    • Secondarily adapted to control buoyancy

      • Height in the water column

    • Can still be used for gas exchange, somewhat.

Level 6 for chordates

• Lobe-fin

  • Ex. Lobe finned fish ex. Coelecanth

  • Robust fins w/ heavy bony support structure.

  • Scientists- say the lobe-fin is for navigating through shallow, heavily vegetated waterways. (now found in underwater caves)

Level 7 for Chordates

• Legs

  • Ex- Amphibians

  • “Two lives”- juvenile stage w/ gills in water adult stage w/ lungs on land.

  • Water dependent reproduction- egg is permeable → the embryo acquires water and nutrients from the environment. 

  • Fish ribcage for lateral protection only.

  • Ribcage- lateral protection and comes through the weight of the internal organs

  • Sprawling posture= ectothermy, cold bloodedness

Level 8 for chordates

•  Amniotic Egg

  • Ex- Reptiles and Birds

    • Reptiles- 

      • Amniotic egg- shelled and waterproof

      • Water and nutrients already inside. 

      • The egg (yolk)

      • Reproduction no longer water dependent 

      • Internal fertilization- fertilization must occur before shell forms.

      • Ribcage- LP + support + breathing 

    • Two major lineages of Reptiles

      • 1) Lepidosaurs- Snakes and Lizards- 

        • (and ichthyosaur and plesiosaurs)

      • 2) Archosaur- Crocodile and Birds 

        • (and dinosaurs and pterodactyls)

    • Birds- 

      • Arose from small bipedal carnivorous dinosaurs. 

      • Feathers- 

        • Probably organically adapted for insulation. 

        • Probably secondarily for sexual selection. 

        • Much later adapted for flight.

        • Upright posture- endothermy

Level 9 for chordates

•  Milk

  • Mammals

    • Upright posture= endothermy (warm bloodedness.

    • Diaphragm for breathing.

    • Hair and fat for insulation

    • Three major groups

      • 1 Monotremes- echidna and platypus

      • ** lay eggs. Mammary glands, but no nipples. Babies lick milk off the mothers coat. 

  • Marsupitlas 

    • Short gestation, followed by “birth” of an altricial (underdeveloped) offspring. 

    • It climbs into the pouch and is attached to a nipple.

  • True Mammals (placentral)

    • Long gestation, followed by birth of a precocial (developed) offspring. (running)

Two types of behavior?

1. Instinctual (innate) and learned.

Instinctual (innate) behavior?

• a behavior that is not based on experience with the environment. 

  • * Most instinctual behavior can be modified by learning.

  • Some instinctual behavior cannot be modified.

Fixed Action Patterns?

• behavioral responses that must be carried out to completion regardless of any new information from the environment. 

  • Sign stimulus- an environmental cue that triggers a FAP.

What other behaviors may be innate?

• Reproduction 

• Grooming

• Suckling

Learned behavior?

1.  behavior that is based on experience with the environment

Imprinting

• an association of self or of safety formed in a critical time period following birth.

Habituation

• absence of response to once relevant stimulus. 

Spatial Learning

1.  Using local landmarks for orientation 

• Foxes need to remember where they buried their food

Cognitive Mapping

1. regional orientation for large-scale migration. 

• **Can be instinctual. How do they know where the north star is?

• Can be learned- socially

Associated Learning

1. based on positive or negative feedback from the environment. (trial and error)

Social learning

1.  watching and mimicking others. (elephants migrating, sending out alarm calls)

Problem Solving

1.  inventive behavior in a new situation (crows and dolphins and chimpz)

What is communication?

• A signal intended to change the behavior of the receiver. 

Selection favors signals that benefit_____________________?

• both sender and receiver. 

Communication display does

• Provides context to a behavior. 

• *Reduces the likelihood of physical fighting.

• Physical fighting can injure or kill all participants, including the winner. 

• Threat (Agonisitic) Behavior?

• Intraspecific - to establish hierarchy

• Interspecific- to deter a predator/ threat. 

  • To preserve a resource

Tactile Display?

•  involve touching

Deception?

• one organism uses a signal inappropriately for its own benefit

Sexual Selection: 2 things

Sexual Dimorphism and courtship display

• Sexual Dimorphism as a signal conveys the age and health of the ____. 

• male

Courtship display

•  as a behavior

Mating Systems: 3 of them

Polygyny, Monogamy, Polyandry

Polygyny

•  one male mates with many females.

  • A group of females allows a male to join for protection.

  • A male controls a resources; he’ll share it with females

  • Both of those mean→ the male gets exclusive mating rights.

  • *Most common in mammals- 

    • Developing offspring are inside the female, so there's nothing for the male to do.

Monogamy

• pair bond– one male & one female (seasonal or lifelong)

  • *90% of bird species

  • The developing offspring are in the nest and even after hatching, requires constant protection and feeding.

Polyandry

• one female mates with many males- only seen in a couple species of birds.

  • *Deception- all the offspring are from one father.