Chapter three

Question 1

Behavioral genetics

Answer 1

The study of the role of heredity in behaviour

Question 2

Three principles of behavioral genetics

Answer 2

1) Behaviors come from many genes, not just one or two, the relationship between genes and behavior is complex
2) By studying twins and adoptees, or by manipulating genes in animals can help separate behavior caused by environment and behavior caused by genes
3) The environment influences how and when genes affect our behavior

Question 3

Twin Studies

Answer 3

Research into hereditary influences involving comparing fraternal and identical twins

Question 4

Adoptive studies:

Answer 4

adoptive people are compared to their biological and adoptive parents

Question 5

Twin- adoption studies

Answer 5

Research into twins, both fraternal and identical, who were adopted and raised apart and those who were raised together

Question 6

Gene-by-environment study

Answer 6

to study heritability, it allows researchers to assess how genetic differences interact with the environment to produce certain behaviours in some people but not in others

• studies parts of the genome itself and examines how different variants act with different kinds of environments to produce different kinds of behaviours
• variation example: the same gene in different people might differ in how many particular DNA sequences it has.

Question 7

What is the genetic sequence antisense?

Answer 7

A synthetic DNA sequence used to block the expression of a gene

Question 8

What is a knockout?

Answer 8

a small animal that has had a specific gene removed

Question 9

What is a transgenic?

Answer 9

an animal that has had a foreign gene inserted from its genome

Question 10

What is epigenetics?

Answer 10

the principle that genes can be turned off or on without change to the sequence of DNA

Question 11

Example of epigenetics?

Answer 11

When we eat or drink certain things and sometimes when we exercise, molecular tags known as methyl groups can get attached to specific nucleotides in the DNA, targeting cytosines. These tags can turn off certain genes

Question 12

Real life example of animal epigenetics?

Answer 12

rats that lick their offspring produce less stressed-out babies
changes the way their stress gene is expressed

Question 13

What does the central nervous system contain

Answer 13

brain and spinal cord

Question 14

what does the peripheral nervous system contain?

Answer 14

the somatic and autonomic nervous systems

Question 15

What does the autonomic nervous system contain?

Answer 15

the sympathetic and the parasympathetic nervous system

Question 16

What part of the NS is “fight or flight”?

Answer 16

the sympathetic nervous system

Question 17

What part of the NS is “rest and digest”?

Answer 17

the parasympathetic nervous system

Question 18

What do glial cells do

Answer 18

structural support of CNS and PNS

90% of the brain cells are glial cells

Question 19

What is the soma?

Answer 19

The cell body

Question 20

What is the myelin sheath?

Answer 20

substance that insulates the axon of some neurons, at regular intervals along the axon’s length

Question 21

What is the myelin sheath made of?

Answer 21

oligodendrocytes and schwann cells

Question 22

What are the gaps in the myelin sheath?

Answer 22

nodes of raviner

they functino for electrical impulses to jump along the axon much quicker

Question 23

What is “white matter” in the brain

Answer 23

part of brain with myelinated axons

Question 24

Grey matter?

Answer 24

cell bodies, dendrites and small unmyeinated neurons

Question 25

the neuron before the synaptic cleft is called what

Answer 25

the presynaptic neuron

Question 26

the neuron after the synaptic cleft is called what

Answer 26

The postsynaptic neuron

Question 27

Sensroy neuron

Answer 27

recieve incoming sensory information

Question 28

motor neurons

Answer 28

take infor/commands from brain to muscles

Question 29

interneurosn

Answer 29

communicate with other neurons, relaying information

Question 30

What are the two jobs of a neuron

Answer 30

1) transmit a message to its target neuron across synapse

2) transmit messange along itself

Question 31

What is a graded potential?

Answer 31

chemical communication at the synapse

Question 32

action potentials?

Answer 32

all signal to travel all the way down the neuron

Question 33

what generates graded potentials?

Answer 33

neurotransmitters when they are released into the synaptic cleft, all started by action potentials

Question 34

What generates action potentials?

Answer 34

graded potentials, some of the time, produce action potentials in the next neuron

Question 35

what is resting potential and what does it mean

Answer 35

resting potential of the neuron is -70mV

this means the inside of the cell is slightly more negative than the outside of the cell

Question 36

transmitter dependent channels

Answer 36

open when a specific neurotransmitter binds to it

Question 37

voltage-dependant channels

Answer 37

open when there is a change in the electrical gradient along the neuron

Question 38

What are synaptic vesicles

Answer 38

sacs neurotransmitters are packaged in in the presynaptic terminal

Question 39

depolarization

Answer 39

when the charge difference between the inside of the neuron and the outside of the neuron lessens. \the inside of the neuron becomes less negative

Question 40

hyperpolarization

Answer 40

when the charge difference between in the inside of the neuron and the outside of the neuron becomes greater.
the charge on the inside of the neuron becomes more negative

Question 41

threshold?

Answer 41

-55mV all or nothing, if it reaches this action potential happens

Question 42

What happens when an action potential happens

Answer 42

1) sodium channels open allowing Na
this temporarily raises the charge to 40mV
2)as the impulses travel down neurons. potassium, K, channels open which allow K to exit the neuron
restoring the resting potential
3)This continues until cell is super-negatively charged “refractory period” when the neuron cannot generate another action potential
4) once action potential reaches terminal, third ion gate opens

Question 43

Enzymatic degradation

Answer 43

the process of deactivating a neurotransmitter at synapse where specific enzymes alter the neurotransmitters so nothing can bind to receptors

Question 44

presynaptic reuptake

Answer 44

removing excess neurotransmitters from the synapse, packaging them in special proteins and returning them to the presynaptic neuron for future use

Question 45

action or graded potential potential for a long distance message

Answer 45

graded potential