Lesson 5 - Nervous System and Sense Organs Flashcards
there are different types of __ __ across the invertebrate groups
nervous systems
adaptations in invertebrates
special sensory
Three types of nervous system in invertebrates
- Simple nervous system
- Ganglia-based nervous system
- Complex nervous system
mini brains of simpler animals
ganglia
nervous systems contribute to __
adaptations
Simple Nervous Systems
- Nerve Net
- Radial Nerve System
- a diffuse network of neurons with no central brain
- simple reflexes and behaviors
- present in cnidarians
nerve net
what does the nerve net allow
simple reflexes and behavior
where are nerve nets present
cnidarians
nerve nets allow cnidarians to respond to stimuli in __ __
every direction
- nerve cords without a true brain
- central nerve ring that coordinates movement
- allows coordination of limbs independently
- present in echinoderms
radial nerve system
radial nerve system
radial nerve cords without a true brain
coordinates movement in radial nerve system
central nerve ring
where is the radial nerve system present
echinoderms
Ganglia-Based Nervous Systems
- Bilateral type
- Centralized brain, segmented ganglia
- bilateral symmetry with nerve cords and cerebral ganglia
- ganglia acts as a simple brain coordinating body movement
- require a more organized system
- present in flatworms
bilateral type
bilateral type
- bilateral symmetry with
- nerve cords and
- cerebral ganglia
acts as a simple brain coordinating body movement in the bileral type
ganglia
where is bilateral type present
flatworms
Parts of the bilateral types
- cerebral ganglia
- longitudinal nerve cords
- transverse commissure
- peripheral nerve plexus
- complex behaviors due to more developed nervous systems
- present in arthropods
centralized brain, segmented ganglia
what do organisms with centralized brain, segemented ganglia have
complex behaviors
where are centralized brain, segmented ganglia present
arthropods
example of advanced behavior of organisms with centralized brain and segmented ganglia
- rapid motion
- swimming
- flying
Parts of centralized brain, segmented ganglia
- brain
- ventral nerve cord
- segmental ganglia
- advanced nervous systems with large brains and optic lobes
- capable of learning, memory, and problem solving
- develop eyes similar to vertebrates
- observed in cephalopods
complex nervous system
what does the complex nervous system have
- large brains
- optic lobes
what is the complex nervous system capable of
- learning
- memory
- problem solving
what did the organisms with complex nervous systems develop
eyes similar to vertebrates
where can complex nervous systems be observed
cephalopods
Sensory Adaptations in Invertebrates
- chemoreception
- photoreception
- mechanoreception
- thermoreception
- hydroreception
- detecting chemicals in the environment
- e.g. antennae in insects
chemoreception
example of where chemoreception can be found
antennae in insects
- detecting light using simple eyes or compound eyes
- e.g. insects, mollusks
photoreception
example of where photoreception can be found
- insects
- mollusks
- sensing physical stimuli, such as touch and pressure
- e.g. tactile hairs in arthropods
mechanoreception
example of where mechanoreception can be found
tactile hairs in arthropods
- detecting temperature changes
- e.g. pit organs in some arthropods
thermoreception
example of where thermoreception can be found
pit organs in some arthropods
detecting level of moisture
hydroreception
Inverts with Specialized Sensory Systems
- insects
- cephalopods
- crustaceans
specialized sensory system in insects
compound eyes
what do compound eyes provide
- wide field of vision
- detect fast movements
each of the optical units that make up a compound eye, as of an insect.
ommatidium
parts of the ommatidium
- facet
- lens
- photoreceptor
specialized sensory system in cephalopods
eyes with advanced lens systems
what do the eyes with advanced lens systems for
sharp vision underwater
specialized sensory system in crustaceans
statocysts
what are statocysts for
detecting balance and orientation in water
Different types of invertebrates which adapted to extreme environments
- deep-sea invertebrates
- desert invertebrates
- hydrothermal vent invertebrates
adapted to detect faint light or bioluminescence
deep-sea invertebrates
e.g. of deep-sea invertebrates
deep-sea squid
enhanced chemoreception to detect water sources
desert invertebrates
e.g. of desert invertebrates
desert ants
- reduced reliance on vision
- adapted to detect chemical gradients
hydrothermal vent invertebrates
Groundwater invertebrates’ adaptations:
ice caves & sub-glacial aquifers
- cold tolerance
- cryoprotectants
Groundwater invertebrates’ adaptations:
thermal & hot springs
- heat tolerance
- heat shock proteins (HSP) increase
- hormonal regulation by catecholamines
Groundwater invertebrates’ adaptations:
lava tubes & volcanic caves
- resistance to hypoxia
- salinity tolerance
- tolerance to H2S
Groundwater invertebrates’ adaptations:
sulfide-rich aquifiers
- regulating internal H2S levels
- avoidance and exclusion
- symbiosis with bacteria
what did octopuses demonstrate according to a case study
- problem-solving
- tool use
- ability to escape from enclosures
what did complex brain structure allow in octopus
learning and adaptability in varied environments
