Theme 2 Flashcards
What’s the difference between paraphyletic, polyphyletic, and monophyletic?
Monophyletic- is all sister taxa and ancestor included in group.
Paraphyletic- ancestor included in group, but not all sister taxa, one or more missing.
Polyphyletic- common ancestor not included in group.
What are Opisthokonts?
Is a clade of organisms, includes choanoflagellates, fungi, and animals
What are choanoflagellates?
A organism that belongs to the clade of opisthokonts, single celled, and paraphyletic.
In the opisthokonts, what choanoflagellates more related too?
They are more closely related to animals then fungi.
What process intially created animals?
Gastrulation
What is gastrulation? Describe it.
A process in which a digestive cavity as well as a two layered embryo forms.
The process begins with a colony of flagellate protists, then some cells begin to specialize for feeding, and then cells cave in forming the digestive cavity as well as a two layered embryo.
What are the seven features of animals (Opisthokonts), explain them.
Multicellular eukaryote
Chemoheterotrophic- eat other things to digest chemicals which they then use for energy to build molecules using organic carbon.
Cell membranes contact adjacent cell membranes (no cell walls)- cell membranes all touch at cell cell junctions.
Motile (at some life stage)- some animals are sessile, but at one point all animals were motile.
Oxidative phosphorylation to supply ATP
Sense and respond to the environment
Diploid stage is dominant (usually), haploid short lived
What three diagnostic characteristics are only found in animals (Opisthokonts)?
- Develop from a Blastula
- Have Certain extracellular matrix molecules (e.g. the proteoglycan collagen)
Have Certain cell-cell membrane junctions
What is a blastula?
When a cell develops you start of with fertilized cell that divides, becomes a hollow ball of cells and is called a blastula. All animals go through blastula stage during early development.
What is an example of extracellular matrix molecules?
molecules in/near the plasma membrane, example proteoglycan collagen.
What are cell-cell membrane junctions?
Are structures that allow contact/adhesion between cells.
What are three types of cell-cell membrane junctions? Describe them.
Tight junctions- are in vertebrates (formed by fusion of plasma membrane proteins)
Septate junctions- are in invertabraes
These two junctions keep things out
Desmosomes are leaky- allow fluid between the cells
Gap junctions allow some things to move across cells, mainly electrical current, and small molecules. Are cylindrical array of proteins that give access between cells.
Name and Describe 5 Kingdom Plantae traits
Multicellular eukaryote
Photoautotrophic (mostly)
Cell walls
Sessile
Alternation of generations life cycle
haploid (gametophyte) stage alternates with a diploid (sporophyte) stage
both are prominent/multicellular
Photoautrophic- provide food to themselves by sunlight. Each cell has a cell wall with these, has membrane and cell wall. Plants are rooted where they are growing, however stay in one place.
Plants have alternation of generations life cycle, alternated between haploid and diploid stage.
Both gametophytes and sporophyte are big and multicellular whereas ours are single celled.
What are the three sister taxa in kingdom plantae?
Green algae and landplants, red algae, and Glaucophytes (unicellular algae)
What are trace fossils?
Are foot prints/belly traces- basically signs of life tracked through mud.
What organisms developed photosynthesis? What does this mean?
Glacuocystophytes, red algae, green algae, land plants, diatoms, brown algae, dinoflagellates, apocomplexans, cercozoans, cryptophytes, haptophytes, euglenids. All came from different clades, so capture of plastids def happene dmore than once.
What’s the difference between opisthokonts and plantae (How do cells diverge)?
Cell structures are different, plant cells have everything opisthokonts cells do, except they also have a vacuole, cell wall, and chloroplasts. Plants can be photoautotrophic, animals directly can’t.
Name 3 animals that can “photosynthesize” indirectly and describe how they do it.
Elysia chlorotica- This snail eats algae that are photosynthetic and keep its in its digestive track, allows light through its digestive track and then gains energy from algae which uses light to produce products.
Spotted salamander- secretes algae into its eggs, important as it provides extra oxygen for eggs, eggs give off CO2 as waste product that feeds algae.
Corals- happens when water gets too warm and they expel symbionts which bleaches corals, the symbionts are photosynthetic organisms that are in their tissues.
How are plants mobile, what is the defintion of phototropic.
- Plants don’t need to move to get energy and carbon.
- Are sessile but can move by:
Grow up/down/laterally
Phototropic- move in direction of light
Move in response to physical stimuli ex: touch me nots)
Disperse pollen/seeds
What’s an example of plants moving?
Plants shift north as climate is warming, can see this in spruce. Sending offspring further north which allows them to move through generations.
What some consequences of animals needing to move?
Need mechanisms to be mobile, these mechanisms are derived by features such as muscles, nervous system (get you where ur going), digestive system (allows you to process food after eating, excretory system- allows you excrete waste, skeletal system- muscles need to attach to something to move, limbs- need appendage such as limbs or tentacles, allow you to work against environment, need higher metabolic rates as we move fast.
What are some examples of sessile animals?
Barnacles, coral, tube worms, mussles
How do sessile animals eat?
Filter feed, have arms that pull food, or though endosymbiosis (an organism lives inside it and brings food to it) ex: choanocyte cells bring food to sponges.
Do sessile animals have a head?
All don’t have a developed sensory sytem, sessile organisms tend to be missing heads as they have no need to search for food. Food is obtained near them.
Are animals diploid or haploid?
Animals have a dominant diploid stage, haploid stage is very small and is unicellular gamete (egg/sperm)
Are plants haploid or diploid?
Haploid (gametophyte) form alternates with a diploid (sporophyte) form
both multicellular and large
How do we classify organisms?
Use to classify them based on their characteristics ex: morphology, behaviour, heritable traits.
Now classify by descent/DNA
When naming species do they all have latin last names?
Yes
Does phylum porifera have nervous system?
No
What phylum do we belong too?
Phylum chordata, clade craniates
What three types of tissue are found in animals?
ectoderm (tissue on outside of embryo), endoderm (tissue lining intestine) and mesoderm (tissue between the two).
What does diploblastic mean? What symmetry do they have?
organisms that are diploblastic have only ecto and endoderm. Radial symmetry (can be cut any way)
What dos triplo blastic mean? What symmetry do they have?
Mean organism that has three tissues, mesoderm, endoderm, and ectoderm. They have bilateral symmetry, can only be cut length wise.
Which organisms are more prone to cephalization?
triploblastic/bilateral organisms
Name the characteristics of phylum porifer- sponges?
No true tissues- problem in figuring out where they are in tree- don’t know if tissues are ancestral or derived. If blended reaggregate to same form.
Are asymmetrical
What type of organisms have more HOX genes? triplo or diploblastic.
Triploblastic, More complex animals on the phylogenetic tree have a greater number of Hox genes
How do we differentiate between bilateral(triploblastic) organisms ceoloms?
How they subdivide their body categories
What are the three ways bilateral/triploblastic organisms subdivide their body categories? Describe them
coelomate- body cavity (ceolom) is lined with only mesoderm (peritoneum form)
acoelomate- all tissues endo, ecto, and meso touch, no ceolom
pseudocoelomate- endoderm is not lined with mesoderm, therfore body cavity is bordered by endoderm and mesoderm.
The gut lined by endoderm is not free floating, is attached.
What two types of bilateria development are there?
Protostome and deuterostome
How do you identify ( 3 factors) whether a bilateria organism is proto or deutetostome?
How do the embryonic cells divide?
How does the coelom form?
How does the digestive tract develop?
How do embryonic cells divide in protostome/deuterostome?
in protostomes at the 8 cell stage, the orientation of the cells are spiral and are determinate. Meaning that if you take the cell out it’s end goal is already decided. You can’t take it out and grow a new snail embryo.
n deuterostomes at the 8 cell stage, the cells are indeterminate so you can take one cell and it can go through cleavage itself and create a new embryo.
Cells are radial- planes are parallel.
How does the ceolem form in protostomes vs deuterostomes?
In protostomes, mesoderm that forms will branch off and split and form shizoceolem.
In deuterostomes, folds of archenteron forms enterocoelous coelem. Ceolem forms as archenteron begins to fold outwards and mesoderm borders the ceolems.
What is blastapore?
Blastapore is first region that forms during gastrulation stage, is the opening on archenteron (ancient gut) and where the folding first occurred in the gastrulation stage.
How does the digestive tract develop in protostomes vs deuterostomes?
Blastapore forms the mouth first if protosome, and then during gastrulation the anus is formed later.
In deuterostomes, the anus is formed first and mouth is formed second.
What does nerve chord do in deuterstomes vs protostomes?
Nerve cord wraps around digestive tract in protostome
In deuterstome- have dorsal nerve chord, brain does not surround digestive tract.
What two groups are protosomes further divided into?
Lophotochozoans- filter feed and have a trochozoa larva
Ecdysozoans- shed external cuticle to grow
What is the process of shedding in ecydozoans called?
ecydsis- sheds external cuticle to grow.
What does trochazoa larvae look like?
view picture on slide 34 for ans
What are some other markers that allow you to identify species taxonomy?
Body segmentation- example metameric segmentation( repeating segments)- lets you know it’s in chordates- arthropods
Molecular evidence- ex mitochondrial dna you only inherit from mom, lets you trace back lineages in order to catagorize.
Name traits of phylum Ctenophora
Sister group to all other animals
Gelatinous body
‘Combs’ are plates of fused cilia projecting out like a comb, used in locomotion
Have biradial symmetry mix of bilateral and radial symmetry.
Name traits of phylum porifera
Asymmetrical
Para(beside)zoans – no true tissues- still have structure with outer layer body wall and in this body wall have spicules (may be made of cilia and may not be)
Sessile as adults
How do sponges feed?
Are filter feeders, Bring food in through collar/pores (opening) by trapping it in mucus and do phagocytosis, send water out through osculum.
Why are sponges part of kingdom animalia if they have no true tissues/ are sessile?
Because they lost characteristics by becoming sessile.
What organisms make up Phylum Cnidaria
Include Jellyfish, sea anemones, coral, hydra
What are traits of Phylum Cnidaria
Radial symmetry, diploblastic
What are body forms in radial animals?
Body forms are developmental phases, different taxa emphasize one or the other as dominant
What are the two body forms of cnidaria?
Polyp and medusa, Polyp- is cessile cnidarian, will anchor on rock and tentacles will reach out.
Or medusa- will swim and get food that way.
Polyps are like upside down medusas.
How do cnidarian get food?
The modified cilium senses food though stimuli, Cells on ends of tentacles called nematocysts, eject a stinging thread, the thread is coiled in cells that contain nematocysts- cnidoctyes. When a prey item is reached, the coiled thread is ejected and grabs onto prey and pull it into the mouth/anus where it can be digested.
What are two specific examples of cnidarians?
Portugese man of war and box jellyfish
What is phylum rotifera and how do they feed?
-Sister group to Lophotrochozoa and Ecdysozoa
- Are small, multicellular, and aquatic
- the head carries a corona (crown) of cilia that draws a vortex of water into the mouth, which the rotifer sifts for food. Mastax grinds it to be digested.
Name major phyla in lophotrochozoa, what do they all share in terms of symmetry and type?
Phylum Platyhelminthes (flatworms)
Scavengers, predators, ectoparasites, endoparasites (liver fluke, tapeworms)
Phylum Mollusca
Clams, oysters, scallops, mussels, snails, nudibranchs, slugs, limpets, octopus / squid / nautilus
Phylum Annelida (segmented worms)
Earthworms, marine bridle worms, leeches
All of them
Describe traits of phylum platyhelminthes?
elminthes means worm.
These have a gastrovascular cavity, works as both head/anus but still classified as protostomes.
Are acoelomate- no space between cavity and other tissue.
Are really flat, they exchange gasses across surface of body.
They have protonephridia which allow them to manage osmotic pressure.
How do platyhelminthes eat?
They have a head, ganglia are collection of neurons, and have eyespots that allow for detection of light. They orient towards light and detect it. They have the gastrovascular cavity, foods pulled in through the pharynx and into the cavity, food gets pulled in and gets digested through the gastro cavity (big area).
Feed by excreting digestive juices out of pharynx once they find food source, and they break it down outside of body and pull the chunks into the GI tract and then it gets further broken down in the cavity by digestive juices.
Describe Phylum Mollusca
*body plan with three main parts:
–Muscular foot – allows for movement
–Visceral mass – contains all internal organs
–Mantle - drapes over visceral mass, secretes the shell
*Feed using rasp-like radula, Radula is what allow snail to scrape things of other rocks/substrates. Is rough and will great substrate its on an pull food off of it.
Name 4 types in Phylum Mollusca
Chitons, bivalves, gastropods, and cephalopods.
Describe Phylum Annelida?
annelids have bodies composed of a series of fused rings = segmented worms
Have a true ceoloem
examples: Earthworms. marine worms, leeches
Describe Phylum nematoda
20,000 found species, are everywhere in all environments, are parasitic. Example: roundworms
Describe Phylum Arthropoda
Insects, crustaceans, spiders, etc.
*Segmented with jointed appendages
*Hard exoskeleton
Head segment is jointed, cephalothorax
If you dont have jointed legs you can’t lift yourself of the ground.
Important to us and other organisms- pollinate most of our crops, can carry diseases, many are parasitic, are a major food source for humans and crustaceans.
Which phylums are bilaterally symmetrical deuterostomes?
Phylum Echinodermata
Phylum hemichordata
Phylum chordata
What composes phylum echinodermata?
Echino (spiny) dermata (skin)- all spiny skin forms
Starfish, urchins, sand dollars, brittle stars, sea cucumbers, and sea lillies
What comprises phylum hemichordata?
acorn worms
What comprises phylum chordata?
Supbphyla Urochordata, Cephalochordata and Vertebrata
What 5 features are present in all chordates?
notochord, pharyngeal gills slits, dorsal hollow nerve cord, segmented muscle/post-anal tail ( we’ve lost this tail).
Phylum Echinodermata have what features?
Are bilateral symmetrical as larvae, become radial as adults, have a water vascular system and tube feet.
Phylum hemichordata have what features?
Called half chordates because- they have pharyngeal gill slits, dorsal nerve chord.
Mlclr data put them with worms rather than us are referred to as acorn worms.
has Stomochord- stiffens the body
Describe features of phylum chordata
All have 4 characteristics
Notochord (is red structure)
Dorsal, hollow nerve cord (neural tube)
Pharyngeal gill slits- are slits in the perforated pharynx
Segmented muscles with post-anal tail
When did the notochord develop, where is it in humans?
is developed before nervous system, in us our spinal disks integrate into it.
Where did our pharyngeal gill slits go?
In mammals- they don’t persist as slits, they get sucked into neck structure. Happened early on as some people still keep these in mutations.
What are some features specific to subphylum cephlachordata?
Gill slits are for filter feeding.
Cephalochordates notochord goes all the way to tip of snout.
In vertebraes it stops before the head develops.
How does subphylum urochordata feed?
bring water in and filter feed through saliva, bring water in through pharynx and mucus traps food particles.
How does subphylum urochordata develop to adult?
During its transformation to adult formation you lose tail structure and are left with cessile gut.
Whats the common name for subphylum urochordata?
sea squirts
What animals comprises phylum chordata?
fishes, amphibians, lizards, snakes, turtles, birds (most diverse group is song birds), mammals
Describe different types of fishes in subphylum vertabrata
Bony fishes are most diverse group within vertebrates.
Are jawless- hagfishes and lamprey.
Hag fishes have an defense system- if a fish tries to bite them they’ll slime the biting fish- its mouth and gills gets stuffed and can’t breathe.
Have cartilegounous fishes- includes chimera, rat fishes, saw fishes-
Have bony fishes- most diverse group
What types of mammals are there in phylum vertabrata
Mammals- egg laying mammals, have marcupials (pouch mammals), and placental mammals like us.
