What are animals Lecture- 15 Flashcards
What is the first characteristic of animals?
They are multicellular.
What is a metazoan?
Metazoans means “Later -animals”
What does the root word “meta” and the root word “zoo’ mean?
Meta means = later
Zoo means = animal
What are single celled animals called?
Protozoans
What is the second characteristic of animals?
They lack cell walls
What is the third characteristic of animals?
They are chemoheterotrophic
what does it mean to be a chemoheterotrophic animal?
It means that you cannot make your own carbon-based food souse. They get it from carbon molecules made by other organisms
What is the fourth characteristic of animals?
They are mostly sexual
What is the fifth characteristic of animals?
They are animate: meaning they are capable of moving entire multi cellular body in at least one stage of life.
What is the first characteristic that is found exclusively in animals?
They posses extracellular collagen
What is the second characteristic that is found exclusively in animals?
They posses 3 types of intercellular junctions.
What are the three types of intercellular junctions found in animal cells?
Tight junctions
Desmosones
Gap junctions
Where are Homeobox genes found?
They are present in eukaryotes
What is the third characteristic that is found exclusively in animals?
Some animals control anterior to posterior development sequence of embryo,
Within animals what is the primary Homeobox gene?
Hox genes
What type of animal has no Hox genes?
Sponges and ctenophores
True or false:
Most animals share similar patterns of fertilization and early emberotic development
True.
What does the word
“anisogamy” mean?
Small motile sperm, large nonmotile eggs.
What does the root word “an” mean
Not
What does the root word “iso” mean?
Same
diploid zygote intilally undergoes a number of mitotic cell divisions without growth of cells between divisions.
What is this process called?
Undergoing “cleavage”
What is a blastula?
The secound stage of zygotic development, where the zygote becomes a hollow ball of cells.
What is gastrilation?
The third stage of zygotic development. It is when the blastula invaginates (folds inward on itself) at one end.
forming a Gastrula
What does the root word “gaster” mean?
Stomach
Gastrula have two defined layers, what are they?
An ectoderm (outerlayer)
An endoderm (inner layer)
What is direct development?
This occurs when embryos gradually develops towards adult form without sudden changes in morphology.
What is indirect development?
This involves one or more intermediate stages called Larva whoes morphology and behavior differs greatly from sexually mature adult stages.
What is an example of indirect development?
Butterfly life cycle.
How many extant animal phyla exist?
There are roughl y 35.
Is there any relationship between these Phyla?
There is some connects that are agreed upon by old and new views.
Is there any disagreement about the connects between animal phyla?
YES LOTS HOLY SHIT
What is the first traditional way to group animal phyla.
Characteristics of basic body plan, and nature of embryonic development.
