6. Form And Function Of Animals Flashcards
What are protists?
A diverse collection of Eukaryotic organisms that do not fit into animal, plant, bacteria, or fungi groups
What are the 3 domains of life?
- Eukarya
- Bacteria.
- Archaea.
What are 2 broad categories of living organisms?
- Prokaryotes
- Eukaryotes
What are the 4 components of the cytoskeleton?
- Microtubules.
- Centrosome.
- Intermediate filaments.
- Microfilaments.
What do microtubules do?
Form the miotic spindle and maintain cell shape.
What are microfilaments?
Fibrous proteins that form the cellular cortex.
What is a centrosome?
A microtubule- organising centre.
What are intermediate filaments?
Fibrous proteins that hold organelles in place.
What are animals?
Multicellular heterotrophic eukaryotes with tissues developed from embryonic layers.
What is a heterotroph?
An organism that obtains its nourishment and energy by consuming organic matter from other organisms, as opposed to producing its own through photosynthesis or chemosynthesis.
What are the 3 main germ layers?
- Ectoderm.
- Mesoderm.
- Endoderm.
What are embryonic layers?
Distinct tissue layers that develop during the early stages of embryogenesis and give rise to various tissues and organs as the embryo develops.
Also known as germ layers.
What are tissues?
A group of cells that have a similar structure and that function together as a unit.
What are organs?
Structures made up of two or more tissues organised to carry out a particular function.
Approximately how many animal species are there?
1.3 million to 10 million
What are Hox genes?
Homeobox genes only found in animals that set up the correct positioning of the body parts of the animal during embryo development.
What are homeotic genes?
Genes that ensure that the formation of the animal’s shape occurs correctly (regulate morphogenesis).
What are homeobox genes?
A subtype of homeotic genes that are key in regulation of morphogenesis.
When was the last common ancestor of animals?
Approximately 770 million years ago.
What species was the first ‘split’ from the common animal ancestor?
The porifera (the sponges).
What is the proposed common evolutionary ancestor of all animals?
The choanoflagellate protists.
Because of their similarity to sponge choanocyte cells
What is phylogeny?
The evolutionary lineage and relationship history of organisms, depicted through branching patterns and common ancestors.
What is a lineage called when it evolves early and remains unbranched from the evolutionary root?
A basal taxon.