Biology Exam 3

Phylogenies

graphic represented of the relationship of organisms due to common descent

How are phylogenies  constructed?

synapomorphies

Synapmorphies

found in two or more taxa present in their most recent common ancestor but missing in more distant ancestors

How are phylogenies tested?

by hypothesis based on a data set

What do incorrect phylogeny result to?

loss of trait which leads to paraphyletic grouping and convergent evolution which leads to homology leading to synapomorphy

Branch

line representing a population through time

Root

The most ancestral branch in the tree

TIP (terminal node)

endpoint of a branch

Node (fork)

point within the tree where a branch splits into two or more branches

Polygamy

indicates that insufficient data were available to resolve which taxa are more closely related

Polyphyletic grouping

comes from convergent evolution homology a trait that gets lost

monophyletic grouping

known as a linage or clade (ancestral and descendent)

synapomorphy

a shared trait by two or more taxa and is derived through evolution from a common ancestral

Homology

similarity in organisms due to a common ancestry

* trait that is shared throughout

Homoplasy

similarity in organisms due to reasons other than common ancestry

* trait that is not shared throughout

sister taxa

pair of terminal taxa and/or clades that branch from a common node and are often considered closely related

What do we not infer in a phylogenies?

time and amount divergence unless it says it explicitly in the figure caption

Haden Eon

liquid water formation and earth formation

Archaean Eon

* Photosynthetic cells
* Origin of life
* oxygen photosynthesis

Proterozoic Eon

* Photosynthetic
* eukaryote fossil
* rock contain oxygen

Oxygen was absent but O2 spiked when?

2\.5 billion years ago

Multicellular life (plants/ animals/ fungi) evolved recently when?

0\.6 billion years ago

Cambrian

ocean life

Ordovician

this was when plants and fungi invade land

Triassic

first mammals, dinosaurs

Devonian

first insect

Carboniferous

amniotes (lizards) 

What is the fate of all species

extinction

* natural as speciation

When does excitation occur?

at low amounts and constantly through out history (background extinction)

background extinction

environmental or ecological factors disadvantage in relation to other species. Species that would ne expected to go extincted

Mass extinction

humans are the strongest evolutionary factors currently operating at a global scale due to habitat loss, climate change, and pollution.

Biggest extinction

Permin extinction which involved a volcano eruption

Most famous extinction

K/T which killed all the non-bird dinosaurs.

* end of the Cretaceous period

Most recent extinction

quaternary period of the sixth extinction (under way)

* human impact

Adaptive radiation

a single linage rapidly provides many descendant species with a wide range of adaptive forms and new niches

What is the highest point of animal diversity

Cambrian period, this adaptive radiation of animals is called Cambrian explosion

* O2 increased which burst levels in animal evolution

Relationship between extinction and adaptive radiation

* extinction event leads to adaptive radiation
* more diversity = less extinction

Catch-22

approach is limited because we only study what we can grow, if we cannot grow it then it didn’t exist

* microbes are diverted but can only study it by isolating it and growing them in culture 

Kach’s postulates

1. microorganisms must be observed every case of the disease
2. it must be isolated and grown in pure culture
3. must reproduce the disease
4. must be recovered from the diseased animal

Germs cause

disease but more often they don’t cause harm because without them we would survive.

Bacteria cell wall

peptidoglycan and some have outermsmbrane (gram-negative somewhat resistant to antibiotics)

What do antibiotics do to bacteria?

kill or stop them from growing

Why does fungi and bacteria produce antibiotics?

have an advantage when it comes to competing for resources, to kill off their competition.

Bacteria’s role in global oxygen

Cyanobacteria (also chloroplasts) allows cellular respiration through photosynthesis.

* perform oxygenic photosynthesis

Bacteria and archaea role on nitrogen cycle

responsible for the movement of nitrogen atoms through ecosystems around the globe

* bacteria in soil or in plant roots convert nitrogen gas into environment

Haber Basch Ammonia Process

machine that you put air into and it goes under heat and pressure to produce ammonia to be used in the fields for plants this allows:

* more food production
* cause fertilization to flow into ocean and cause algae to grow then die which allow bacteria to decompose the dead algae which takes oxygen out of the water killing fish

How do bacteria share genes?

1. transformation
2. transduction
3. Conjugation

Transformation of genes in bacteria

naturally take up DNA from the environment that has been released by cell lysis

* dead cells released into environment

Transduction

when viruses pick up DNA from one prokaryotic cell and transfer it to another cell

Conjunction (sex)

when genetics info. is transferred by direct cell-to-cell contact

* bacteria swap directly
* genetic information occurs

Biofilm

a complex community of bacteria enmeshed in a polysaccharide-rich, extracellular matrix that allows the bacteria to attach to a surface

Ex: teeth, touchscreen

Archaea

unicellular prokaryotes distinguished by cell wall made by polysaccharides, plasma membrane, and ribosomes and RNA

Who are more closely related to archaea?

eukaryotes

Hypothesis regarding to origin to life

indeterminable…all are everyone’s common ancestors

Endosymbiotic theory

theory that mitochondria and chloroplasts evolved from prokaryotes (bacteria) that were engulfed by host cells and took up symbiotic existance

Cyanobacteria evolved to what?

chloroplast

* engulfed and later eventually allow for photosynthesis to occur

Proteobacteria evolved to what

mitochondria

* allow ATP production and cellular respiration

Unicellular eukaryotes in global food webs/ecosystems (the role being played

* eukaryotes make up the base of the food webs
* Most photosynthesis occurs in the ocean
* too many unicellular eukaryotes can increase high rates of decomposition and decrease O2

How do red tides occur?

caused by too many primary production in ocean

* overuse of fertilizer which gets into ocean. Fertilize algae which results in an out of control of production of algae (increase of primary production). Algae dies drops to the bottom and get decomposed by bacteria. Bacteria plays a role in cellular respiration which decreases oxygen killing aquatic life (dead zone) comes from food production.

How do fungi digest?

heterotrophs; digestion happens on the outside

What do fungi eat?

they’re saprophytic; eat dead stuff, particularly wood

* secrete enzymes of dead things → break down → absorb nutrients

Linchen

are mutualistic partnership between fungi and algae (bacteria)

* fungi and algae took a lichen to each

Yeast

single cell form

Mycelia

multicellular web-like moss of hyphae with indeterminate growth

Hyphae

any fungus growing as a multicellular form

fruiting body

a reproductive structure for dispersing offspring (spores) via wind

* Example: via wind

Mycorrhizal

fungi that lives in close association with plant toots

* help plants grow and resist bacteria

Why are fungi parasitic?

form symbiotic relationship with other living organisms

Ex: zombie ant, infect crops and other plants

Why are fungi predatory?

some fungi produce hyphae for prey capture and nutrient uptake some are predators of animals (ants)

Why are fungi mutualistic?

two organisms work together each benefiting from the relationship

Ex: mycorrhizal and plants

Fungi reproduction

this is very unique because each individual is its own sex and can mate with whoever.

* reproduce asexually and sexually
* are haploid dominant (mitosis)

In the reproduction of fungi what two events occur?

* plasmogamy: cell fuse (cytoplasm)
* karyogamy: fusion of nuclei

What affects our biology?

when taking antibiotics for bacteria diseases that will not affect our biology. However, taking medication of fungal disease will affect our biology because fungi are closely related to our own biology due to have a common ancestor.

Ectomycarrhizal fungi

cover host plant root’s but do not enter the root cell

Arbuscular mycorrhizal fungi

enters the plant’s root cell

* direct contract with plasma membrane of root cell

Recognize the plant tree

__Organisms__

GAly = Green Algae

Married = Mosses

For = Ferns

Good = Gymnosperms

Apples = Angiosperms

__Traits__

==S==he = stomata

==V==en==T==s = vascular tissue

==S==o = seed

==F==requently = flower

Stomata adaptation

* Cuticle = waxy layer that prevent loss of water from leaves and stem
* Stomata = have pores that open and close that allow gas exchange in photosynthetic tissues
* CO2 goes in, O2 n H2O

Vascular tissue

* allows rapid movement of water and support height
* this needs to be dead to be able to move water really fast

What type of vascular tissue is fern and seed plants (gymnosperms)?

Tracheids

Seed adaptation

Diploid (2n) sporophyte generation goes to a haploid (n) gametophyte generation

Seed adaptation to terrestral environment

1. protective waterproof cover (seed coat)
2. Nutrients and nutrient delivery
3. occurs in absence of water

Fern and Moss + Water

* need water to be able to fertile
* sperm swim to egg (diploid) → spores get dispersed in wind → transported and become haploid (n) in next generation

Pine trees and flowers

* Pine tree: don’t need water to reproduce has pollen (microspores) that form and get blow by wind and pollenate another plant
* flower: attract insect to move gametes around to pollenate other plants

why do fruits move offspring away from parent?

due to competition

Pollination syndrome

* flowers attract insect/animals to move games around
* plant attract animals to move offspring around

The stuck in plant evolution

plants cannot get up and run away when an organisms attacks their leafs so they have toxins and other resources to help them fight off organisms that attack them.

* this later became our medication

Services plant provide towards are ecosystems

erosion control, atmospheric O2, food, and temp. modulation

Plant domesticated

* dependent on humans for their survival and reproduction since they’ve been modify and are in need of human help to protect them from deadly insects and organisms.
* Ex: Nightshade flower are toxic but humans choose the least aggressive nightshade towards humans to domesticate it to provide food by taking the toxicity away

Are humans domesticated?

Yes

What does GMO do to plant?

increase fitness

Choanoflagellates

are the closest living relatives to animals

All animals are?

multicellular; cells lack cell wall but have communication between cells and all differentiate in the jobs they do inside the organisms

* Ex: sponge

Heterotrophs

all animal obtain carbon compounds by eating

How are animals and fungi similar?

organisms that are multicellular are both heterotrophs that digest and break down nutrients.

* One organisms digest nutrients from the inside and the other from the outside

Basal Clade of all animals is?

the sponge

What is the difference between basal clade and chanoflagellates?

doesn’t have a multicellularity (true tissue)

Symmetry

key morphological aspect of an animal’s body plan

Bilateral symmetry

(most animals) only have one plane of symmetry and tend to have a long, narrow body

* Ex: Starfish, annelid worm
* divides into a left and right

Radial Symmetry

at least two planes of symmetry or more

* Ex: Body of a cylinder or disk organism

What symmetry is diploblastic?

radial symmetry