H6 Holland- What is a vertebrate?

0.0(0)

Studied by 0 people

Call Kai

Learn

Practice Test

Spaced Repetition

Match

Flashcards

Knowt Play

Card Sorting

1/3

There's no tags or description

Looks like no tags are added yet.

Last updated 8:54 AM on 4/30/26

Name	Mastery	Learn	Test	Matching	Spaced	Call with Kai

No analytics yet

Send a link to your students to track their progress

4 Terms

New cards

what extra features did vertebrates evolve?

bony living skeleton

made of secreted collagen fibres + calcium phosphate crystals
osteoblasts make bone, osteoclasts break down bone, and osteocytes are strain/crack sensors
vertebra are formed from fusing of bone produced at the sclerotome, the inner part of the somites (dorsal, segmented mesoderm- unlike the ventral, lateral plate mesoderm)

neural crest cells

individual cells migrating from the inner section of the infolding of the dorsal hollow nerve cord
these form: sensory nerves to the skin, pigment cells, nerves in the gut for peristalsis, autonomic nervous system, some blood vessel muscle, and the bone + cartilage of the skull

red blood cells

invertebrates only have a few cells in the blood for phagocytosis, but vertebrates have red cells with haemoglobin

adaptive immune system

the innate immune system of invertebrates recognises common pathogens, but the adaptive immune system in vertebrates changes with the environment by dna rearrangement
this is due to antibody genes and t-cell receptors

these traits allowed early vertebrates to evolve into big, active, swimming, hunting predators

<p><strong>bony living skeleton</strong></p><ul><li><p>made of <strong>secreted collagen fibres + calcium phosphate crystals</strong></p></li><li><p><strong>osteoblasts </strong>make bone, <strong>osteoclasts </strong>break down bone, and <strong>osteocytes </strong>are strain/crack sensors</p></li><li><p>vertebra are formed from fusing of bone produced at the <strong>sclerotome</strong>, the inner part of the <strong>somites </strong>(dorsal, segmented mesoderm- unlike the ventral, lateral plate mesoderm)</p></li></ul><p><strong>neural crest cells</strong></p><ul><li><p>individual cells <strong>migrating </strong>from the inner section of the <strong>infolding </strong>of the dorsal hollow nerve cord</p></li><li><p>these form: sensory nerves to the skin, pigment cells, nerves in the gut for peristalsis, autonomic nervous system, some blood vessel muscle, and the<strong> bone + cartilage of the skull</strong></p></li></ul><p><strong>red blood cells</strong></p><ul><li><p>invertebrates only have a few cells in the blood for phagocytosis, but vertebrates have red cells with <strong>haemoglobin</strong></p></li></ul><p><strong>adaptive immune system</strong></p><ul><li><p>the innate immune system of invertebrates recognises common pathogens, but the adaptive immune system in vertebrates <strong>changes </strong>with the <strong>environment </strong>by<strong> dna rearrangement</strong></p></li><li><p>this is due to antibody genes and t-cell receptors</p></li></ul><p></p><p>these traits allowed early vertebrates to evolve into big, active, swimming, hunting predators</p><p></p>

New cards

what features of vertebrates became more complex?

sense organs of the head

olfactory- chemical sensing
optic- light sensing
otic- mechanical sensing

larger brain

forebrain- olfaction + thinking in some vertebrates
midbrain- optic lobes
hindbrain- neural crest cells in this region make the cartilagenous gill skeleton:

pharyngeal slits

supports gills in fish
the first slit is the jaw bone, the second is a jaw support bone

these traits allowed early vertebrates to evolve into big, active, swimming, hunting predators

<p><strong>sense organs of the head</strong></p><ul><li><p>olfactory- chemical sensing</p></li><li><p>optic- light sensing</p></li><li><p>otic- mechanical sensing</p></li></ul><p><strong>larger brain</strong></p><ul><li><p>forebrain- olfaction + thinking in some vertebrates</p></li><li><p>midbrain- optic lobes</p></li><li><p>hindbrain- neural crest cells in this region make the cartilagenous gill skeleton:</p></li></ul><p><strong>pharyngeal slits</strong></p><ul><li><p>supports gills in fish</p></li><li><p>the first slit is the jaw bone, the second is a jaw support bone</p></li></ul><p></p><p>these traits allowed early vertebrates to evolve into big, active, swimming, hunting predators</p><p></p>

New cards

describe the phylogeny of the vertebrates

vertebrates are a subphylum of the chordate phylum in the deuterostomia clade of bilaterian animals

the first lineage to evolve was the agnatha (lamprey + hagfish), before the gnathostomata developed jaws + paired fins:

chondrichthyans- cartilagenous fish eg. sharks + rays
osteichthyes- bony fish
- actinopterygians- ray-finned fish eg. most fish
- sarcopterygians- lobe-finned fish + tetrapods (terrestrial)

the ‘fish’ is a paraphyletic group/grade, not a clade- it contains the most recent common ancestor but not all the descendants (no tetrapods)

<ul><li><p>vertebrates are a <strong>subphylum </strong>of the <strong>chordate phylum </strong>in the <strong>deuterostomia clade </strong>of <strong>bilaterian </strong>animals</p></li></ul><p></p><p>the first lineage to evolve was the <strong>agnatha </strong>(lamprey + hagfish), before the <strong>gnathostomata </strong>developed <strong>jaws </strong>+ paired fins:</p><ul><li><p><strong>chondrichthyans</strong>- cartilagenous fish eg. sharks + rays</p></li><li><p><strong>osteichthyes</strong>- bony fish</p><ul><li><p><strong>actinopterygians</strong>- ray-finned fish eg. most fish</p></li><li><p><strong>sarcopterygians</strong>- lobe-finned fish + tetrapods (terrestrial)</p></li></ul></li></ul><p>the ‘<strong>fish</strong>’ is a <strong>paraphyletic </strong>group/grade, not a clade- it contains the most recent common ancestor but <strong>not all the descendants (no tetrapods)</strong></p>

New cards