Notes 11 Flashcards
What are the characteristics that define the kingdom Animalia?
Nutritional mode, cell structure and specialization, and reproduction and development.
Plants are ____trophs
Autotrophs
Fungi are ___trophs.
heterotrophs (secrete enzymes, absorb nutrient)
Animals are ____trophs.
Heterotrophs. They cannot construct all their own organic molecules. They obtain organic molecules from the food that they ingest and use enzymes to digest the food within their bodies.
Animals are multicellular _____.
Animals are multicellular eukaryotes. They lack cell walls and instead protein external to cell membrane provide structural support to animal cells and connect them to one another. Must abundant is collagen which is only in animals.
Cells of most animals are organized into what?
Cells of most animals are organized into tissues, groups of similar cells that act as a functional unit.
What are the 2 defining tissues in animals?
Muscle tissue (movement) and nervous tissue (conducting nervous impulses) are unique defining characteristics of animals.
What type of reproduction do animals use?
Most animals reproduce sexually and the diploid stage is the longest of the life cycle. Metotic divison produces haploid sperm and egg cells. Most species have small flagellated sperm that fertilizes a larger non motile egg forming a diploid zygote.
How does early embryonic development in animals occur?
First,a sperm fertilizes an egg and the zygoate undergoes a series of mitotic cell divisions called cleavage. The 8 cell embryo is formed by 3 rounded of cell divisions. Cleavage produces a multicellular stage called a blastula. Blastula is a hollow ball of cells surrounding a cavity called the blastocoel. Following blastula stage is the process of gastrulation. One end fold inward producing layers of embryonic tissue (ectoderm=outer layer, endoderm=inner layer). The resulting developmental stage is called the gastrula. A pouch is formed by gastrulation called the archenteron which opens to outside via blastopore. The endoderm of the archenteron develops into tissue lining animals’ digestive tract.
Most animals have at least how many larval stages?
At least 1.
What are the characteristics of a larva?
-sexually immature
-morphologically distinct from adult
-different food
-possibly different habitat than adult
Animal larvae eventually undergo what to become juvenile?
Metamorphosis.
Juveniles have what characteristics?
Resembles an adult but is not yet sexually mature
What type of genes are limited to animals?
Most animals and only animals have hox genes regulating development of body form. Although the hox family of genes is highly conserved, it can produce a wide diversity of animal morphology.
What is a body plan?
A body plan is a particular set of morphological and developmental traits integrated into a functional whole- the living animal. Body plans are a way to compare and contrast animal features. Animal body plans have evolved over time.
what is the most identifiable characteristic of animal bodies?
A basic feature of animal bodies is therir type of symmetry or absence of symmetry. Many sponges lack symmetry altogether and some have radial symmetry like a flower pot. Any imagainry slice through the central axis divides the animal into mirror images. Have oral of aboral sides but no LR/BF. 2 sided symmetry is called bilateral symmetry. Bilateral symmetrical animals have a dorsal side and a ventral side, a L and R side, and an anterior and posterior end.
Where is sensory equipment in an animal?
Many also have sensory “equiptment” concentrated at the anterior end, including the brain (development of a head), which is called cephalization. Ends with sense organs and brain encounters environment first: advantages like detecting prey and predators.
Radial animals are one of what 2 things?
Radial animals are often sessile (living attached to a substrate) or planktonic (drifting or weakly swimming). Their symmetry allows them to meet the environment equally well from all sides.
T or F: Bilateral animals usually stay in one place.
False. Bilateral animals often move actively from place to place and have a central nervous system, which allows them to coordinate complex movements involved with crawling, burrowing, flying, and swimming.
Animals body plans vary based on what?
the organization of the animal’s tissues
What are true tissues in animals?
In animals true tissues are collections of specialized cells isolated from other tissues by membranous layers.
Sponges and a few other groups lack what?
True tissues.
What is gastrulation?
Gastrulation is an early developmental process in which an embryo transforms from a one-dimensional layer of epithelial cells, a blastula, and reorganizes into a multilayered and multidimensional structure called the gastrula.
All organisms besides sponges go through a process called what?
In all other animals the embryo becomes layered through the process of gastrulation.
As development progresses, these layers, called
____ layers, form the various tissues and organs
of the body.
germ layer
What is the germ layer covering the
embryo’s surface; gives rise to outer
covering of the animal, and in some phyla
to the central nervous system?
Ectoderm
What is the endoderm?
the innermost germ layer and
lines the developing digestive tube, called
archenteron; also gives rise to lining of
digestive tract and organs such as liver and
lungs of vertebrates
What animals only have 2 germ layers? (echo and endoderm)
Diploblastic.Includes cnidarians and a few other groups
What animals also have a third germ
layer, the mesoderm layer between
ectoderm and endoderm?
Triploblastic.
Triploblastic animals have what kind of symmetry?
Bilateral symmetry. Includes flatworms, arthropods, vertebrates. Mesoderm forms muscles and most other organs
between the digestive tract and the outer
covering of the animal
Most triploblastic animals possess a ___ ____.
Body cavity
A true body cavity is called a what?
Coelom
What is a coelom?
A fluid or air-filled space between the digestive tract and the outer body wall.
A true coelom is derived from what?
The mesoderm
What are coelomates?
Coelomates, such as earthworms, are animals that possess a true coelom, a body cavity completely lined by tissue derived from mesoderm.
What is a pseudocoelom?
A pseudocoelom is a body cavity derived from mesoderm and endoderm. It is fully functional.
Triploblastic animals possessing a pseudocoelom are called pseudocoelomates. (ex. roundworms). Triploblastic animals that lack a body cavity are called acoelomates. (ex. planarians)
What are the functions of body cavities?
-Its fluid cushions the suspended organs which helps prevent internal injury
-In soft bodied animals (earthworms) the coelom contains non compressible fluid that acts like a skeleton.
-Cavity enables internal organs to grow and move independently of outer body walls.
Based on early development, many animals can be categorized as having how many developmental modes?
one or 2, protostome and deutrostome
How are protostome and deuterostome distinguished?
These are distinguished by differences in cleavage, coelom formation and fate of blastopore.
Many animals with protostome development undergo ____ cleavage. The planes of cell division are ______ to the vertical axis of the embryo. ____ cell stage, smaller cells centered over ______ between larger underlying cells. _____ cleavage rigidly casts or determines the
developmental fate of each embryonic cell very early.
Many animals with protostome development undergo spiral cleavage. The planes of cell division are diagonal to the vertical axis of the embryo. Eight cell stage, smaller cells centered over grooves between larger underlying cells. Determinate cleavage rigidly casts or determines the developmental fate of each embryonic cell very early
In deuterostome development, they have _____ cleavage: cleavage planes are either _____ or _____ to vertical axis of embryo. ___ cell stage tiers aligned, ______ cleavage each cell produced by early cleavage divisions retains capacity to develop into a ______ ______.
In deuterostome development, radial cleavage:
cleavage planes are either parallel or perpendicular to vertical axis of embryo. Eight-cell stage tiers aligned, Indeterminate cleavage each cell produced by early cleavage divisions retains capacity to develop into a complete embryo
In protostome development, splitting of solid
masses of mesoderm forms what?
The coelom
In deuterostome development, what buds
from the wall of the archenteron to form the
coelom?
mesoderm
When does the blastopore form?
The blastopore forms during gastrulation and connects the archenteron to the exterior of the gastrula.
In most animals a second opening forms at what positon to the gastrula?
The opposite end
In protostome development, the blastopore becomes what?
In protostome development, the blastopore becomes the mouth: “first mouth”
In deuterostome development, the blastopore becomes what?
In deuterostome development, the blastopore becomes the anus; mouth is formed from second opening “second mouth”
Zoologists recognize how many dozen animals phyla?
Zoologists recognize about 3 dozen animal phyla, phylogenies now combine morplogical, molecular, and possila data.
Sponges are what kinds of animals?
Basal
What is a clade with true tissues/animals?
Eumetazoa
Most animal phyla belong to what clade?
Bilatera.
