Chapter 2A & Chapter 2B Flashcards
What is a monophyletic tree?
It is a set in a phylogenetic tree that contains a single organism and all of its descendants.
What is a polyphyletic tree?
This is a set where organsims from clades are selected although they do not have a common ancestor.
What is a paraphyletic tree?
It is a set in a phylogenetic tree where a common ancestor and almost all of its descendants are chosen.
What is a blastula?
This is a hollow cell of blastomeres that animal cells originate from after fertilization through cleavage.
What is a chemoheterotroph?
These are organisms that attain different chemical sources and feed off of them.
What is an autotroph?
This is an organism that is able to synthesize its own food.
What is a tight junction?
These are found in invertebraes and are regions where cell membranes connect to each other.
What are desmosomes or anchor junctions?
These are junctions that attach to stretching muscles and consist of cells that adhere to mass.
What are gap junctions?
These are direct channels that allow the flow of ions and small molecules and lead to electricity.
Would organisms with a cell wall be good predators?
No, because the cell wall hinders mobility and the ability to bring down food.
How do animals that are sessile attract prey?
1.) Symbiosis
2.) Filter feeding
3.) Ambush
How are organisms classified?
- Genetics
- Morphology
- Behaviour
- Physiology
What is the Linnaeous system?
This was a taxonomical hierarchy of organisms ranging from domain (broad) to species (specified) and the closer you get to the species level the more similar the organisms get.
What is bilateral symmetry?
This is when an organism can be split in half, has 3 layers the ectoderm, mesoderm, and endoderm, also it allows for cephalization.
What is cephalization?
Having the senses condensed in an area.
What are protosomes?
These are bilateral organisms that have their first opening as their mouth.
What are deuterosomes?
These are bilaterial organisms that have their first opening as their anus.
What is the ectoderm?
This is the exterior layer.
What is the endoderm?
This consistutes the internal organs such as the GI or digestive tract.
What is the mesoderm?
This is the layer of muscles tissues that coordinate the rest of the body system.
What is the formatting for the naming?
The genus name is always capitalized, italicized, or underlined.
What is a pseudocoelomate?
This is known as a false fluid filled cavity that lies between the endoderm of the gut and the mesodermal structure.
What are acoelomates?
These are organisms that do not have a coelem thus they lack a fluid filled cavity.
What is a coelom?
It is a fluid filled cavity of the body that separates the internal organs from the endoderm.
How do sponges get their food?
The sponges have a lining called the spongeocoel which consists of porocytes where the water comes in through and passes by the occulum which has sensory cilia and when there is an uptake of water there is a current that takes food in.
What is the purpose of ejecting the nematocyst for a cnideria?
The nematocysts are curled up in the cnidocytes and when stimulated it is ejected as a way to attach on to another organism and attempt to prey on it.
What is the medusae?
This is the upper pointy half of the cnideria which provides mobility.
What is the polyp?
This is the lower pointy half of the cnideria which provides sessility.
What is the rotifera’s corona?
This is a crown of cilia that creates a whirmwhole of food or water and pulls it into the mouth of the organism.
How do mollusca create a shell?
They have a structure called the mantle which secretes calcium carbonate to generate the shell.
What is the scolex of an annelida?
These are hooks or links that the tapeworm uses to attach itself to the structure and the body of the host so it can feed off of it.
What is ecdysis?
This is the process of the ecdysozoans shedding their layer of chitin that protects them but hinders their growth.
When are the ecdysozoans the most vulnerable?
When their chitin armor is shedding.
What is the point of an arthropods exoskeleton?
- Protection
- Hydration
- Connect limbs/muscles
What are the 3 main clades of the deuterostomes?
1.) Phylum enchinodermata
2.) Phylum hemichordata
3.) Phylum chordata
Why is the enchinodermata considered bilateral?
Even though the adult enchinodermata is not bilateral the young is.
What is the water vascular system and tube feet?
There is a short tube that connects to the ring canal which surrounds the esophagus and the ring branches into 5 arms each canal is connected to tube feet that protrude through holes in the plates.
What are the 4 characteristics of the chordata?
1.) Notochord
2.) Dorsal nerve cord
3.) Pharyngeal gill slits
4.) Segmented muscles with the post-anal tail
Humans do not have pharyngeal gill slits?
Yes, we did in the embryonic phase.
What are pedcellariae?
These are small pincers at the base of the spine that help the sea stars remove debris.
What is the notochord?
This is a flexible rod that develops from the mesoderm dorsal to the digestive system.
What are the gill slits for?
This is the paired opening system where water passes in it is carried to a large space and then food is pushed in and waste is pushed out.
How do urochordata regulate their functions?
Water passes in through the gills into the atrium and then waste passes out through the atrial siphon.
How do cephalochordata regulate their functions?
Water passes in through the gills into the atrium and then waste passes out through the atriopore.
What is a vertebrae?
An organism with a backbone or spine.
What is an organisms genome?
The entirety of its DNA all of the chromosomes it posssesses and the DNA sequence is identical in every cell of that organism.
What leads to diverse phenotypes?
Different genes being turned on or off during the transcription phases.
What is the difference between Hemp and Cannabis?
Cannabis contains higher quantities of THC which get you high while hemp is a seed that does not have THC.
What would happen if the common ancestor between the plants and animals is where the plastid arose?
Then animals would have chloroplasts and would be green.
Are plants sessile?
Most but those that can move do so very slowly.
What are the 3 reasons of why we classify organisms?
1.) To understand diversity
2.) Organisms can be grouped together based on traits
3.) Evolutionary lineage information
Why study flies/weed?
Although the organisms themselves are different they can be used for research.
what does multicellularity lead to?
The specialization of cells into tissues => organs
Why is understanding organisms important?
For the sake of research and determining groups.
What are the common traits of almost all land plants?
- Eukaryotes
- Almost all are photoautotrophs
- Multicellular
- Sessile or stationary
- Cell walls
- Alternation of generations life cycle
- Embryo (sporophyte) retained on the gametophyte tissue
Are all plants photoautotrophs?
No, all plants do contain plastids however some lack chlorophyll although they do not all photosynthesize for example the monotropa uniflora.
What is the primary cell wall?
It consists of cellulose and is common to all plants, surrounds the plasma membrane, and it is rigid yet flexible.
What is the secondary cell wall?
It consists of lignin which anchors the cellulose fibres and is found in the xylem and the sclerenchyma.
What is the most common misconception?
The cell wall provides the rigidity to the plant cell.
What is hypertonic?
There is more water outside then inside the vacuole = plasmolyzed state.