Nervous System (CNS and PNS) Flashcards
(34 cards)
Do sponges have a nervous system?
No
Describe the Cnidarians CNS. What are they?
- Have nerve nets- where neurons are spread apart
- Lack a brain
- Jellyfish
Describe the Annelids CNS. What are they?
- Well developed brain
- Ganglia in each segment
- Earthworms
Describe the Arthropods CNS. What are they?
- Brain
- Ventral nerve chord-double row of ganglia nervee chords on ventral and dorsal
- Segmental ganglia-in the thorax and abdomen provide nerves to the appendages, dorsal muscles, sense organs, and heart.
- Decentralized nervous system
- Crab
Describe the Cephalopods CNS. What are they?
- Ganglia in each arm
- Ganglia in body
- Brain
- Squid
Describe the Vertebrates CNS. What are they?
- Highly cephalized
- Hollow nerve chord on dorsal (back) side of body- the spine
- Animals
What are the four CNS protective barriers?
- Bone coverings
- Protective meninges
- Cerebrospinal fluid
- Blood-brain barrier
What is bone’s role in CNS protection?
- Brain is covered by skull
- Spinal cord is protected by vertebrae
What is meninges role in CNS protection? 3 types?
- The cranial meninges are layers of connective tissue continuous with the spinal meninges.
- Protect the brain and provide nutrients
- Dura mater-tough outer layer under the skull
- Arachnoid mater- spidery middle layer
- Pia mater- thin layer over the brain
What is cerebrospinal fluids role in CNS protection? 3 functions?
- Circulates through the internal cavities in the brain and spinal cord
- Mechanical- cushions the brain and protects from trauma
- Homeostatic- Removes waste products
- Circulation- Circulates nutrients
What is blood brain barrier’s role in CNS protection?
-a filtering mechanism of the capillaries that carry blood to the brain and spinal cord tissue
- The vascular endothelium around brain capillaries forms tight junctions with the nearby astrocytes.
- Blocks passage of certain substances
What are the three regions of the brain? How are they split up?
- Hindbrain- Controls most reflex responses; Regulates involuntary behaviours
- Midbrain-Coordinate visual, auditory, and sensory information
- Forebrain-Process olfactory (smell) information; Regulating body temp, reproduction, sleeping, eating; Learning and memory
What are the 3 basic functions (divisions) of the hindbrain?
-Medulla oblongata
Reflex centers regulating breathing, heart rate, diameter of blood vessels
Neural pathways between spinal cord and brain
-Pons
Control alertness, sleep and wake, regulates breathing
-Cerebellum Motor coordination (body posture, coordinates locomotion, integrates info from proprioceptors)n
What are the basic functions of the midbrain?
- Tectum- Optic lobes- Processes visual, auditory and touch information.
- Tegmentum- Reflex responses to visual, auditory and touch
Midbrain differences in animals.
- Humans- small
- Other animals are large
What are the basic functions of the forebrain?
- Cerebrum (Basal gangli, Amygdala, Hippocampus)
- Olfactory bulb
- Accessory olfactory bulb
- Hypothalamus
- Epithalamus
- Thalamus
What are the 3 basic functions of the forebrains cerebrum?
Cerebrum= Information processing
- Basal gangli- Movements
- Amygdala- Emotions
- Hippocampus- Memory
What are the basic functions of the forebrains olfactory bulb and accessory olfactory bulb? What secondary structure are these?
- Olfactory bulb- Sense of smell
- Accessory olfactory bulb- Direction of pheromones
- Telencephalo
What are the basic functions of the forebrains thalamus, hypothalamus and epithalamus? What secondary structure are these?
- Hypothalamus- Homeostatic regulation (e.g. body temp, feeding, repro, hunger, and thirst; circadian rhythms, sleep/wake cycles
- Epithalamus- Melatonin secretion. circadian rhythms, regulation of limbic system
- Thalamus- Integrates sensory information
- Diencephalon
What are the cerebrum’s lobes? 4 main and 11 cortical areas.
- *Frontal lobe**
- Primary motor cortex
- Premotor cortex
- Prefrontal cortex (thought)
- Broncas area (speech)
- *Parietal lobe**
- Somatosensory cortex
- Sensory association areas
- *Occipital lobe**
- Visual association areas
- Visual cortex
- *Temporal lobe**
- Olfactory cortex
- Limbic association areas
- Auditory cortex
What is the difference between the right and left hemispheres of the brain?
**Right** imagination holistic thinking intuition arts rhythm nonverbal cues feelings visualization daydreaming
**Left** logic sequencing linear thinking mathematics facts thinking in words
Who is Phineas Gage?
Got a rod driven through head. Destroyed his left frontal lobe
What are the 3 cranial sensory nerves? (PNS)
Olfactory (smell), Optic (vision), Vestibulocochlear (hearing)
What are the 5 cranial motor nerves? (PNS)
Oculomotor (eyeballs and pupills), Trochlear (eyeballs), Abducens (eyeballs), Accessory (head and pectoral region), and Hypoglossal (speech and food)