Problem 1

Question 1

How would you describe evolution

Answer 1

Variations in individuals within species affects the probability of survival

Question 2

What is the difference between homoplasy and homology?

Answer 2

Homoplasy is when different animals have similar characteristics to adapt to an enviroment (i.e. tuna vs. Dolphins)
Homology is similarities due to common ancesters

Question 3

What features are shared by all vertebrate nervous systems?

Answer 3

• development from a hollow neuraltube
• bilateral symmetry
• Hierarchical control
• seperate systems: CNS and PNS
• localization of functions
• creation of the spinal cord

Question 4

What is the encephalization factor?

Answer 4

The encephalization factor is the ratio between the body weight and the brain weight

Question 5

What are some of the explanations for the large increase in relative brain size in humans compared to other species?

Answer 5

The social brain hypothesis, later becomes larger hypothesis

Question 6

What is the social brain hypothesis?

Answer 6

The social brain hypothesis states that human brains have developed more because social interaction and relationships are complex cognitive tasks

Question 7

Why are humans and chimps different dispite 99% identical DNA?

Answer 7

Humans and chimps are different because the location and sequence of genes can still cause differences and which genes are expressed is dictated by many factors. (Specifically the expression pattern of the gene ASPM)

Question 8

What are four types of glial cells

Answer 8

1. Astrocytes: star shaped, provide supplies and regulate bloodflow
2. Microglial cells: clean up cellular debris
   3&4 Oligodendrites and Schwann cells: myelation

Question 9

What is the name of the inital segment of the axon?

Answer 9

Axon hillock

Question 10

What is a dendritic spine and what is its function?

Answer 10

The dendritic spine are the outgrowths of dendrites, the increase the synaptic surface area

Question 11

What is chemical transmission?

Answer 11

Action potentials leading to the release of vesicles containing chemical signals into the synaptic cleft, carrying the message over to the postsynaptic cell

Question 12

What are the levels of structures of proteins?

Answer 12

Primary: polypeptide chain
Secondary: folded structures within the polypeptide
Tertiary: 3D folds
Quarternary: multiple polipeptides folded together

Question 13

What are the two classes of postsynaptic receptors?

Answer 13

Directly and indirectly coupled receptors

Question 14

Explain where neurotransmitters are synthesized

Answer 14

Small neurotransmitters are synthesizef in the synaptic terminal
Big neurotransmitters are synthesized in the cell body

Question 15

Explain how neurotransmission begins in the presynaptic neuron

Answer 15

Neurotransmission begins with an electrical process, the electrical impulse is converted into a chemical signal at the synapses

Question 16

Explain how neurotransmitterd can affect the postsynaptic neuron

Answer 16

The neurotransmitters bind to the receptors of the postsynaptic membrane and initiate changes. The potential of the membrane could become depolarized, this can cause either an EPSP or an IPSP as a result.

Question 17

Explain the difference between classical, retrograde and volume transduction

Answer 17

Classical transduction: starts with an electrical process, converts this to a chemical message which is delivered to the postsynaptic neuron.
Retrograde: the same principle as classical except in the opposite direction, information is carried from the post- to the presynaptic neuron
Volume: transduction through extra chemical messengers spilling over to neighboring neurons (without going past the synapses first)

Question 18

What is excitation-secretion-coupling?

Answer 18

Sodium slows into the synaptic nerve, which causes calcium channels to open, this results in vesicles spilling their chemical content in the synaptic cleft

Question 19

What are signal transduction cascades?

Answer 19

A long string of chemical messages within both the pre and postsynaptic neuron. This involves numerous molecules with the neurotransmitter being the first messenger

Question 20

Is the ion-channel linked system able to activate kinase, phosphatase or both?

Answer 20

Both, it mainly activates phosphotase however it can also cause the phosphorylation of CREB which is kinase

Question 21

How does the second messenger system work?

Answer 21

The first messenger activates the receptor, this causes the receptor to change shape so it is conductive for the G- protein, then the G-protein changes shape to allow the enzyme that synthesizes the second messenger to bind. The enzyme makes the second messenger and the cycle continues

Question 22

How do early genes influence late genes?

Answer 22

Early genes are rapid responders 5o neurotransmitter input, making the proteins they encode. These proteins come together to form a zipper of transcription factor which in turn activates later onset genes.

Question 23

What is chromatin

Answer 23

Chromatin compacts the genome into the nucleus, if chromatin gets strengthened it restricts access to read proteins and thus they can’t be transcribed

Question 24

Which processes take place during neurodevelopment?

Answer 24

1. Neurogenesis
2. Migration
3. Differentiation
4. Synaptogenesis
5. Neuronal cell death
6. Synapse rearrangement

Question 25

How would you explain the increase in brain weigth after birth?

Answer 25

Brain weight increases due to an elaboration of synapses, growth size of neurons, more myelination, additional glial cells, branching of dendrites

Question 26

What factors stimulate adultneurogenesis?

Answer 26

Enriched experiences, learning

Question 27

How do neurons migrate?

Answer 27

Neurons migrate by following radial glial cells, and with the help of Cell adhesion Molecules

Question 28

What is apoptosis?

Answer 28

Natural cell death that occurs when neurons fail to make an adequate amount of synaptic connections, thus when theyre not active enough

Question 29

What are neurotrophin factors?

Answer 29

Neurotrophic factors affect the growth, survival and differentiation of both developing as adult neurons, neurotrophic factors stop apoptosis

Question 30

What are the criteria for neurotransmitters?

Answer 30

1. They should be synthesized by, located in, and stored in the presynaptic neuron prior to release
2. They must be released by the presynaptic neuron when action potentials occur
3. The postsynaptic neuron must contain receptors specific for them
4. When artificiallu applied to the postsynaptic neuron they still elicit the same response