Heterotrophs
Derive organic nutrition externally
Common ancestor are protists

Microbrial eukaryotes

Animals
Eukaryotic
Multicellular
Heterotrophs
Internal processes to break down food.
Most can move (except for sponges).
Heterotrophs
Filter feeders

Sponges

Herbivores

Goats

Predators

Owls

Parasites

Lampreys

Detritivores

Shrimp

Omnivores

Humans

Carnivores

Bats

Cell Surface of an Animal
No cell wall usually
Made of glycoprotein, carbs, proteins, cytoskeleton
Extracellular Matrix ECM
Exists just outside the cell membrane
Contains collagen

Triple-alpha helix

Contains proteoglycans

Proteins + Carbs

Tight Junctions
In animal cells
Epithelial cells
Proteins connect neighboring cells tightly

Prevents leaky gut

Barrs movement of dissolved materials between cells.
Desmosomes
In animal cells
Link adjacent cells tightly, but permit materials to pass in the intercellular space.
Gap Junctions
In animal cells
Let adjacent cells communicate
Allows for sharing ions, signals.
Have connexins (channel proteins) that span into adjacent cell membranes (hydrophilic channel) for sharing nutrients/signals.
Sponges
Are primitive animals.
Filter feefers
Beating flagella moves water
Phagocytosis (choanocytes are phagocytic feeding cells).
Respiration
Structural Spicules
Are monoblastic (one tissue layer)
Sedentary
Spongin - a modified collagen protein
Reproduce sexually (fragmentation) or asexually (sperm).

Anthropods

Antropods
Land or water
Exoskeleton outside the body made of chitin.
Segmented bodies with paried, jointed, appendages.

Crustaceans

Insects Anthropod
Have gas exchange by diffustion
Most have 2 pairs of wings.
Body segments: Head, thorax, abdomen.
Have mandibles
Arachnids Anthropod
4 pairs of appendages = 8 legs
Are all chelicerates (have fangs)
Pointed mouths used for grasping.
  • Not chewing mouthparts
May have hollow celicerae w/ venom.
Tardigrades Anthropod
Tiny water bears, hardy in dormant states.
Are ecdysozoans that molt.

Two Types of Protosomes

Lophootochozoa
Not segmented.
Skeletons are internal, no shedding/molting.

Mollusks

Ecdysozoa
Often jointed.
Molting/shedding insects.
External exoskeleton made of chitin.

Anthropods

Mollusks

Mantle
Fold of tissue secretes calcareous shell for protection.
Mantle Cavity
Contains gills for gas exchange of filter feeding.

Body Cavity Classifications

Acoelomate Anti-Coelomate
Body cavity not fluid.
No internal organs, only gut.
Not a true body cavity, no distinct structure.

Flat worms

Psuedocoelomate Semi-Coelomate
No mesoderm.
Has unorganized internal organs.
Fluid-filled body cavity.
Coelomate True body cavity
Internal organs are organized w/ the mesoderms.
Body cavity lined with mesoderms.

Circulatory Systems

Gastrovascular Cavity
Cnidaria

Sponges, jellies, anenomes

Open Circulatory System
Have hemolyph similar to blood
Anthropods

Snails, clams, insects

Closed Circulatory System w/o an endothelium
Annelids (segmented worms)
Squid, octopus
No red blood cells.
Closed Circulatory System lined with endothelium
Humans, mammals, amphibians, reptiles, birds

Developmental Biology

Gastrulation determines phylogeny of organism.

Blastopore
1st opening during gastrulation.
Gastrulation
Animal egg to 1st ball of cells.
Differentiation of cell layers into ectotherm (outer), mesoderm (middle), endotherm (inner).
Protosomes

Insects

Gastrulation: 1st blastopore develops into the mouth.
Deuterosomes

Humans

Gastrulation: 1st blastopore develops into the anus.

Corals

Light

Bioluminescents
Uses enzymes to create light

Firefly, Corals

Fluorescent
Absorbs, then emits light

Jellyfish

HOX Genes

HOX Genes Homeotic Genes
HOX genes code for HOX proteins.
HOX = developmental/segment genes.

PDM

HOX Proteins
Transcription factors that bind dna to regulate the activity of many target genes at once.
Turn mRNA synthesis on or off to alter protein synthesis.
Matches with sequence in multiple parts of a gene to start (more common) or stop transcription for multiple genes at once.
Motif
? DNA sequence (target)

Metamorphosis

Complete
Changes are dramatic.
HOX genes change from juvenille to metamorphosizing larvel tissues.
Incomplete
Changes are gradual, less dramatic.
HOX genes remain active throughout metamorphosis.