Kingdom Animalia: Overview Flashcards
Definition
An animal is a multicellular, heterotrophic motile organism having cells without cell wall. During embryonic development. It has a blastula stage. It also has well developed organs and cephalization
Name 4 characteristics of this kingdom
1) it is eukaryotic and usually multicellular.
2) it is heterotrophic add the digests food and internal chamber.
3) it lacks cell wall.
4) embryos pass through a blastula stage, which is an early phase in animal embryology, consisting of a hollow sphere of cells surrounding a central cavity
What is the evidence of them being monophyletic?
1) Gene sequences ex. rRna
2) Similar organization and function of Hox genes
3) Cells have unique junctions ex. Tight junctions , desmosomes and gap junctions
5) Have a common set of extracellular matrix molecules ex. Collagen
Who was the ancestor of the animal kingdom and why?
It was a colonial flagellated protist.
1) functional specialization of cells in the colony arose.
2) coordination among cells may have been improved by regulatory molecules
3) differences in derived traits among animal groups are used to study the evolutionarily relationships ex. Paleontology, developmental patterns, morphology, and physiology
Types of classification
Multicellularity
1) permitted increase in size
2) specialization
Types of classification
Tissues
1) Diploblastic: endoderm and ectoderm
2) Triploblastic: endoderm mesoderm and ectoderm
Types of classification
Symmetry
1) Asymmetrical:
- Radial: a plane through the central axis, divides the animals into roughly two mirror image halves ex. Jellyfish. These are diploblastic, and usually slow.
- Bilateral: the body can be split into two mirror image halves by a single plane, running through the midline. These are triploblastic. We use the terms anterior, which means the head, posterior, which means the opposite end to the head, dorsal, which is the backside, ventral, which is the front or belly side.
Types of classification
Cephalization
Definition: organisms to concentrate the sensory and neural organs in an anterior head.
The anterior end encounters the environment first.
Types of classification
Body Cavity (1-4)
1) Acoelomate: the mesoderm fills the blastocoel therefore no coelom ex. Flat worms
2) Pseudocoelom: cavity formed between endoderm and mesoderm ex. Roundworms
3) True coelom: cavity develops by splitting the mesoderm
Importance of Coelom:
4) Support: can act as hydroskeleton, gives support and aids in locomotion.
Types of classification
Body Cavity (5-8)
5) Distribution: coelomic fluids move within the cavity and serve as a circulatory system therefore increase in size ex. Insects
6) Protection: internal organs bulge into the coelom and are protected from being deformed by muscular action. Therefore the organs can move independently ex. Heart
7) More space: ovaries and testicles can expand
8) Induction: endoderm and mesoderm and mesoderm and endoderm are in contact, therefore, interaction of tissue during embryonic development.
Types of classification
Metameric segmentation
Definition: the building of the body from a series of segments ex annelids
Advantages:
1) repetitive segments in the body still allow survival if parts of the body are damaged
2) different segments can move independently
3) increase in body size
4) specialization
Types of classification
Jointed appendages and exoskeleton
1) greater flexibility in movement
2) fusion of body segments into body units ex. Head, thorax and abdomen of insects covered in a rigid exoskeleton
