Exam 3 Flashcards
Sponges
Have mo muscle cells at all , rooted to the ground, They don’t move from place to place.
Jelly Fishes
Have muscles that contract to squeeze a fluid full activity, powering movement by jet propulsion.
Mammals
Have limbs for locomotion which are powered by the coordinated actions of muscles attached to internal skeleton.
Insect
same as Mammals but their skeleton is external.
what are the majority of all animal species?
Insects
What organism is closely related to animals?
Choanoflagellates
choanoglagellates
a group of single cell Eukaryotes
are mostly unicellular, whereas animals are multicellular.
Multicellularity
Is not unique feature of animal, plants and Fungi are also Multicellular.
Heterotrophs
animals, gaining energy and carbon from preformed organic molecules.
Important- separates animals from plants!!!
what do animals cells lack?
Cell wall, allowing cells to move during development and in the adult animal.
What is the difference between animals and plants?
Animals have a pattern of early embryological developments that begins with a hollow ball of cells called the blastula and includes the movement of embryonic cells , usually to form a gastrula. A process unique to animals.
Animals
are Multicellular heterotrophic eukarotyes with a distinctive mode of early development.
Porifera
sponges, an animal phylum characterized by few cell types, not wall defined tissues and no clearly defined plane of symmetry.
Cnidaria
A phylum characterized by radical symmetry, two germ tissues in the embryo, a close internal gastric cavity and well developed tissues but not organs includes Jellyfishes, sea anemones and corals.
Bilateria
Most other animals, including insects, humans and snails shows bilateral symmetry.
Movement of Bilateral symmetry
are able to move horizontal to capture pray, find shelter and escape from enemy
Cephlization
A concentration of nervous system components at the end of the body.
Key feature of body plan of most bilaterian animal, including vertebrate.
Segmentation
The formation of discrete repeating parts or segment in the developing body of many animals.
Drosopphila Melanogaster
Fruit fly, have head, thorax and abdomen.
What three animals are known for showing segmented body plan?
arthropods( insects, spiders, and crustaceans)
segmented annelids
segmented worms
chordates
vertebrates
Why has segmentation evolve?
adaptation to higher mobility.
Diploblastic
Describe animal in which the embryo the embryo have two germ layer, the endoderm and ectoderm, from which the adult tissues develop.
Triploblastic
Describes animals in which the embryo have three germ layer with the mesoderm between the endoderm and ectoderm.
Protostomes (second mouth)
A bilarterain in which the blastopore, the first opening to the internal cavity of the developing embryo, becomes the mouth. The taxonomic name is Protostomia, and the group includes mollusks and arthropods.
Deuterostomes (second mouth)
A bilarterian in which the blastopore, the opening to the internal cavity of the devloping embryo, becomes the anus. the taxonomic name is the deuterostomia and includes human and other chordates.
what are Protostomes
Nematodes( ground worms), arthropods( insects, spiders, and crustaceans). Mollusks ( gastropods, like snails and slugs, bivalves like clams and mussels and cephalopods (squids and octopus). Annelids ( segmented worms) and flat worms.
what are deuterostomes
blastrope becomes the anus and the mouth formes second
includes chordates such as vertebrates and encinoderms, such as area stars, sea urchins and sea sand dollars
what four cells are organized in animal ?
epithelial, connective, muscle and nervous
Tissues
are collection of cells that work together to perform a specific function.
organ
two or more tissues that combine and function together.
epidermis
epithelial tissues
epithelial tissues
A type of animal tissue that provide provide a lining for all the spaces inside and outside the body. it is composed of closely packed cells.
Connective tissues
A type of animal tissues that under line epithelial tissues and is found else where as well it has an extensive extracellular matrix and few cells.
Muscle tissues
A type of animal tissues made up of cells (fiber) that are able to shorten or contract resulting in movement.
Nervous tissues
a type of animal tissue found in the nerve net of cnidarians and in the brain , spinal cord and peripheral nerves of vertebrate. It takes in sensory information from the environment, processes information and send signals to target organs to elicit a response.
organ system
A group of organs that have related functions for example ,the intestine is one organ of the digestive system which also includes the stomach, liver, pancreas and other organ.
Homeostasis
the active regulation and maintenance of a stable internal physiological state in the face of a changing external environment.
Negative feedback
A process of which the output or product of a pathway opposes the initial stimulus so that steady condition are maintained negative feedback often underlies homeostasis in a cell or organism.
set point
A steady state value in homeostatic regulation
A phase of rapid animal diversification that took place approximately 541 million years ago and is documented by the Burgess shale. Most of the major groups phyla of animals that exist today first appeared in the fossil record during this relatively short period of geologic time.
Cambrian explosion
mass extinctions
A catastrophic drop in recorded diversity, which has occurred five or more times in the past 541 million years.
what are haploid gametes
are made of meiosis in animals and but are made by mitosis in plants and fungi.
Asexual reproduction
Binary fission ,budding, fragmentation , parthenogenesis
Binary fission
Bacteria and Archaea
Budding
yeast
Fragmentation
some molds, algae, worms, sea stars and coral
parthenogenesis
a lot of invertebrates and few special vertebrates.
Higher rate of failure
environmental sexual reproduction needs a lot of gametes and eggs.
needs to get eggs close to sperm
Bilaterians (The coelom)
A fluid filled body cavity which cushions the internal organs against hard blows to the body and enables the body to turn without twisting these organs.
Amnions
more freedom from water for reproduction the amnions, a membrane surrounding a fluid-filled cavity that allows the embryo to develop in watery environment.
what are Amnions
reptiles, birds, mammal
Development Animals
development of all animals involves coordinated events from the molecule to the organism level.
lateral development
occurs in distinctive stages
. Larva- (in some) a free living stage different in form from adults
. Juvenile
Adults
One cellular level
there are changes in cell form cell, cell interaction and cell positions
what is unique to animal developments?
Changes in cell position are unique to animal development.
Genetic level development
is regulated by
distinctive bits of genetic code shared across the entire
group of Eukarya
Drosophila eye tissue development
has been stimulated in several areas of the fruit fly body using eyeless’ gene and homeobox proteins that signal development.
EAF- Ediacaran Period
579 million years ago Precambrian, simple shape, many flat, no obvious head or tail.
The Cambrian fossil
541-485 mya the body plans characteristic of most
Bilaterian phyla took shape in a
transition period called the Cambrian
explosion.
Why transition period
It was a relatively short time with a
huge accumulation of new characters – lots of new stuff appearing in a
short time is not normal, hence,
“transition”
Brachiopod Fossils
Ordovician (489–444 mya)
Majority of ‘shells’ would
be from brachiopods, not
a modern mollusk as we
see today – clams, snails,
etc.
