PSY251 V2

Question 1

Somatosensory cortex:

Answer 1

IN the postcentral gyrus, posterior to the central sulcus.

Responsible for processing sensory information.

Question 2

Premotor cortex:

Answer 2

Located in frontal lobe. Organises movement sequences.

Question 3

Motor cortex:

Answer 3

Located in frontal lobe. Produces specific movements.

Question 4

Limbic system.

Answer 4

Made up of the
AMYGDALA
HIPPOCAMPUS
CINGULATE CORTEX.

Regulates
Emotional and sexual behaviours. Memory.
Spatial navigation.

Question 5

Amygdala.

Answer 5

Organises behavioural, autonomic & hormonal responses to a variety of situations, including those that produce fear, anger, or disgust.

Involved in the effects of odours and pheromones on sexual and maternal behaviour.

Question 6

Amygdala Lesions/Animals

Answer 6

Passivity and emotionally unresponsiveness (like “Psychic blindness”).

Can lead to no function for fear.

Can lead to no function for disgust.

Can lead to furious attacks on others (may depend on what parts of the amygdala are destroyed/left intact)

Changes in sexual behavior Amygdala Lesions/Animals

Question 7

Broca’s area.

Answer 7

Located in frontal lobe. Involved in complex speech. Interacts with the flow of sensory information from the temporal lobe. Devises plan for speaking and passes it onto the motor cortex.

Question 8

Medial

Answer 8

Towards middle

Question 9

Lateral

Answer 9

Toward the side

Question 10

Dorsal

Answer 10

Towards top.

Question 11

Ventral:

Answer 11

Towards bottom

Question 12

Anterior

Answer 12

Towards front

Question 13

Posterior

Answer 13

Towards back

Question 14

Nervous system organisation

Answer 14

Question 15

CNS:

Answer 15

Spinal cord, brainstem, and forebrain.

Question 16

PNS

Answer 16

(Peripheral nervous system) made up of the neurons outside of the brain and spinal cord and takes in the somatic, autonomic, and enteric nervous systems.

Question 17

ANS (two a parts and their functions)

Answer 17

The autonomic nervous system pathways exert opposite effects.

Sympathetic: Arouses the body to action though the fight or flight response by increasing heart rate and blood pressure.

Parasympathetic: Prepares the body for rest and digest by reversing the alarm response or stimulating digestion.

Question 18

SNS

Answer 18

Sensory nerves (Afferent) (Posterior in spinal column)

Motor nerves (Efferent) (Anterior in spinal column)

Question 19

Enteric nervous system

Answer 19

Mesh of neurons embedded in the lining of the gut, running from the esophagus through the colon; controls the gut. Communicates with the CNS though the ANS, but mostly works alone.

Question 20

Ependymal cell.

Answer 20

Produce and excrete cerebrospinal fluid.
Sodium chloride

Question 21

Astrocyte cell.
6 things.

Answer 21

Works as a scaffold to hold neurons in place by attaching to blood vessels and neurons.

Connections to blood vessels also serve as a conduit to feed certain nutrients to the neurons.

Secrete a chemical to keep neurons healthy.

Where these connections to the blood vessels occur, the astrocytes communicate to the cells that make up the vessels to close up tightly so as not to allow any toxins into the brain, known as the blood brain barrier.

Communicate from neurons to blood vessels when more nutrients is required to facilitate dilation of blood vessels.

Lastly the astrocyte helps to repair neurons when they are damaged.

Question 22

Microglia.

Answer 22

A glial cell. Make up 20% of all glial cells.

Identify and attack foreign tissue in the nervous system.

Because immune cells cannot enter the brain because of the blood brain barrier, there needs to be another catalyst for getting rid of foreign matter, which is the microglia.

Question 23

Oligodendroglia and Schwann cells

Answer 23

Myelin

Insulate neuronal axons improving conduction speed, and help to feed neuron nutrition.

Schwann cells myelinate (Insulate) in PNS and also help to repair nerve damage with the When the new axon sprouts it follows the path created by the Schwann cells

Oligodendroglia myelinates cells in the CNS

Question 24

Key components of a neurons

Answer 24

Dendritic spines
Soma
Axon
Collaterals
Axon Terminal
Myelin sheath

Question 25

Blood-brain barrier

What can get through?

Answer 25

A barrier that is made from the closing up of the cells that make up blood vessels in the brain to protect from toxins.

Thought to occur because of the astrocyte cells that enclose the blood vessels in the communicate with the blood vessel cells.

Some drugs do carry the right signatures to get through some of the transporter proteins if they mimic that particular substances, other drugs are small enough to pass though places where glucose or oxygen can get though.

Question 26

Cell membrane

Answer 26

Phospholipid bilayer. Remember that protein channels are the things like the ligand activated gates.

Question 27

Resting potential

Answer 27

The point that the neuron is ready to be fired and has achieved electrochemical equilibrium though the use of selective membrane permeability.

Normally around -70mV

More K+ Inside the cell than outside (about 20 times). Na+ voltage-gated channels are closed.

Question 28

Action potentials

Answer 28

Neurotransmitters released from the preceding neuron axon terminals, via the terminal buttons, and bond to the ligand-gated channels (usually on the dendrites) to open them. For the action potential to generate there needs to be enough of these open to bring the membrane potential up to -55mV, this is the threshold. This will happen if enough stimulation from the presynaptic terminal comes though (Normally NT) It does this by allowing in enough Na+ through the ligand gated channels which increases the membrane potential. known as graded potential. Sometimes not enough ligand-gated channels are stimulated, in this case you get a small increase in the membrane potential but not enough to cross the threshold, known as graded potential. If enough stimulus to the membrane potential occurs through the influx of Na+, the Na+ voltage-gated channels will open (happens at about -55 mV). Once the gated channels are opened to the sodium ions, they rush into the cell and bring about a positive charge to the intracellular part of the cell and in turn the membrane potential becomes more positive. Once the membrane potential becomes positive (known as Overshoot, gets to around 40mV) and reaches it’s peak, the voltage gated Na+ channels become inactivated and will not allow in anymore Na+. They become inactivated through a second gate on the Na+ voltage-gated channels, this second gate stops another action potential happening too quickly, and also ensures that the nerve impulse does not travel backwards. The sodium/potassium pumps continue to transfer out the sodium ions in exchange for the potassium ions to ready the action potential to fire again. Nerve impulses are generated along the cell body and down in axon in a cascading manner, as the threshold is reached in one area and Na+ voltage-gated channels open, it raises the membrane potential further along the dendrite/cell body/axon which in turn brings that part up to threshold and opens the Na+ voltage gated channels and so and so forth.

Question 29

Saltatory conduction

Answer 29

Fast propagation of an action potential at successive nodes of Ranvier; saltatory means “leaping.”

Question 30

Golgi bodies

Answer 30

Membranous structure that packages protein molecules for transport.

Question 31

Lysosomes

Answer 31

SACS containing enzymes that break down waste.

Question 32

Tubules

Answer 32

Tiny tube that transports molecules and help give the cell shape.

Question 33

Endoplasmic reticulum

Answer 33

Folded layers of membrane where proteins are assembled.