What is a Vertebrate Flashcards
What are vertebrates
Backbones animals, a subphylum of Chordata
What groups are included in Chordata
Vertebrates, tunicates and cephalochordates
What makes up a vertebrates skeleton
Living tissue with collagen fibres and calcium phosphate crystals (hydroxyapatite)
What are the three main bone cell types and their functions
Osteoblasts – build bone
Osteoclasts – break down bone
Osteocytes – act as strain/crack sensors
What tissue layer forms the hollow dorsal nerve cord in vertebrates
The ectoderm folds in during development
What somites
Segmental blocks of mesoderm that help form vertebrae
What is the lateral plate mesoderm
It wraps around the gut and stomach
What part of somites becomes bone
The sclerotome
Where does the skull come from if somites don’t reach the head
The exoderm (and neural crest cells)
What are neural crest cells
Migratory embryonic cells from the neural tube that form various structures
What can neural crest cells become
Sensory nerves
Pigment cells
Gut nerves
Autonomic nervous system
Some blood vessel muscles
Most of the skull (bones/cartilage from the top of the embryo)
What forms the base of the skull
The first few somites
How do invertebrate and vertebrate blood cells differ
Invertebrates: a few phagocytic cells
Vertebrates: RBCs with haemoglobin for oxygen transport
Why is haemoglobin important
It supports larger body size by transporting oxygen efficiently
What type of immune system do invertebrates have
Innate immune system - recognises common pathogen features
What additional immune capability do vertebrates have compared to invertebrates
An adaptive immune system - antibodies and T-cell receptors via gene rearrangement
Which sense organs became more complex in vertebrates
Olfactory (smell)
Optic (sight)
Otic (hearing/vibrations)
How did the vertebrate brain evolve
Larger forebrain for thinking and smell
Distinct midbrain (optic lobes)
Segmented hindbrain for gill skeletons
What are pharyngeal slits and their function
Slits in the throat supported by cartilage arches. They support gills in fish, one arch evolves into jaw support and later stapes of the ear
How does having a
1. Skeleton
2. RBCs
3. Immune system
4. Head
benefit vertebrate ecology
- enables efficient swimming
- supports an active lifestyle
- allows for survival in varied environments
- bigger brain and senses which allows for better hunting and predation
What kind of lifestyle did early vertebrates evolve into
Active, swimming, hunting predators in marine environments
What is “fish” not a proper group in phylogeny
It doesn’t form a single branch - vertebrates are split into three lineages
What are the 3 major branches of vertebrates
- Chondrichthyans – Cartilaginous fish (light, flexible skeleton)
- Actinopterygians – Ray-finned fish
- Lobe-finned fish + Tetrapods
What do reptiles, birds and mammals share in common
Amniotic eggs - adaption for life on land
