Invertebrate Flashcards
What are the three domains of life?
Bacteria, Archea, Eukarya
What are the 7 animal characteristics? Tell me about them.
- Eukaryotic (nucleus, membrane-bound organelles, cytoplasm)
- Heterotrophic (different forms of feeding)
- Multicellularity
- No cell wall
- Motile at some life stage
- Body cells are diploid (2N)
- Animals are diplontic
What does it mean for an animal to have multiple cells?
1) cells can become specialized to carry out specific functions
2) organisms can have longer lifespan
3) can grow in size
what are the three types of structural support for animals?
1) hydrostatic skeleton (worms, shell-less snails) (just body) (muscles contract against fluid filled cavity)
2) exoskeleton (snails, outside shell)
3) endoskeleton (on inside) (sponges)
what is the reproduction process for animals?
1) meiosis (sperm and egg)
2) fertilization
3) 2N- zygote forms
4) mitosis
What are colonial choanoflagellate protists?
- closest living relative to ancestral animals
- marine
What is the Cambrian explosion?
rapid diversification, many new phyla formed
What are the three pieces of evidence that shows animals are monophyletic?
1) similar gene sequences
2) similar extracellular matrix molecules
3) unique types of junctions among cells
What are the three junctions among cells for animals?
1) tight junction (seals cells together, epithelial tissue)
2) desmosome (connects the cytoskeleton of cells)
3) gap junction (channels between them)
What are ecdysozoans?
a group of animals that grow by ecdysis which is the moulting of their exoskeleton (sheding )
What is coelom?
Internal, fluid filled body cavity, lined up with mesoderm (place for nutrient and oxygen exchange)
What are Hox genes?
group of related genes that specify regions of body, plan along the head-tail axis of animals.
What are the two major processes of embryo development?
1) cleavage (rapid multiple rounds of cell division, forming many cells from one)
2) gastrulation (in-folding forming of embryonic tissue layers)
- first cleavage happens, starts are zygote, 2 cell stage, 8 cell stage, solid ball of cells formed, then form layers called Germ layers
What are the 3 types of germ layers?
1) ectoderm (outer layer, epidermis, nervous system)
2) endoderm (inner, digestive, respiratory tract)
3) mesoderm
Compare Diploblastic Vs Triploblastic
- Diploblastic= 2 germ layers, middle skin (mesoderm, internal organs, muscles, skeletal system)
- Triploblastic= 3 layers, they have archenteron (digestive space) and blastopore (mouth and anus)
What are the three types of body symmetry for animals?
1) asymmetrical - no axis, divides body equally halves
2) radial symmetry - along one plane, can be cut into halves from many angles
3) bilateral symmetry - equal halves from single axis
What is filter feeding (sponges)?
Water and food particles go in via spores and then out of the water canal
What are the three support structures of sponges?
1) Extra cellular matrix (non-cellular, collagen and glycoproteins)
2) spongin (protein fibres, flexible support)
3) spicules (CaC03, Si02, provides rigidity)
What are the two types of asexual reproduction for sponges?
1) fragmentation (external budding, not self-induced, brought on by waves or predators)
2) internal budding (clone of parent)
What is the process of Hermaphroditic (sexual production for sponges)?
sperm and eggs produced in choanocytes or amoebocytes, the sperm is trapped by females and fertilized and then developed in the extracellular matrix, larvae released and it settles
What does cephalization mean?
the concentration of sense organs, nervous control at the anterior end of the body, forming head and brain.
What does protostome mean?
mouth appears before anus during development, coelom forms as a splitting from mesoderm.
what does deuterostome mean?
first opening (blastopore) becomes anus and mesoderm and coelom forms from outgrows of primitive gut
What are the 4 key parts of the body plan of Cnidaria?
1) epidermis (ectoderm)
2) gastrodermis (endoderm)
3) mesoglea (collagen and proteoglycans)
4) gastrovascular cavity (archenteron)
What are the two types of ways that the body of Cnidaria can be oriented?
1) Polyp (sessile - does not move) (shapes like a P, facing up)
2) Medusa (motile) (shaped down like an M)
(most life cycles include both)
How do Cnidaria obtain energy?
- Carnivorous - inject prey w/ toxins and capture prey
- extracellular digestion in gastrovascular cavity
What are the 4 different diverse types of Cnidaria?
1) Hydrozoa (fresh water, no medusa stage, moves by gliding/floating)
2) Scyphozoa (true jellyfish)
3) Cubozoa (box jellyfish)
4) Anthozoa (“flower animals”, retract tentacles in defence)
What are some of the causes of coral bleaching?
it is a stress response to increase water temp, increase UV radiation, pollution, and disease (bacteria).
What are the three types of body cavities for Cnidaria?
1) Coelomate (mesoderm lines entire cavity as a “peritoneum”)
2) Pseudocoelomate (mesoderm lines outside of pseudocoel)
3) Acoelomate (no body cavity, solid except for digestive space)
What are two ways to make coelom?
1) Schizocoely (splitting within mesoderm - protostomes)
2) Enterocoely (mesoderm forms pockets from gut - deuterostomes)