Health and Well-Being ERQ

Genetic Inheritance

the process by which genes are passed form parents to kids

What is another thing that Genetic Inheritence refers to?

the extent to which the kids behaviour is inherited from parents

All cells in the human body have wat?

a nucleus that contains a set of chromosomes

What happens to the long DNA molecule of a chromosome?

its tightly coiled many times around supporting proteins

what is a metaphor that describes what a chromosome essentially is

a “package” that contains folded DNA

What does DNA stand for

deoxyribonucleic acid

What does the DNA do?

store info

What is DNA made up of

a code made upof a long sequence of 4 chemical bases

What are the 4 chemical bases

Adenine to Guanine and Cytosine to Thymine

What happens to the bases

they are paired up making up a sequence of base paits which also allows the DNA to have the structure of a double helix

How is genetic information encoded in DNA?

In the sequence of bases along the DNA strand, like letters in a sentence.

HUman DNA consists of how many bases

3 Billion

What is a gene

a unit of heredity

wat does a gene do?

a region of DNA that encodes info that determines a specific trait or functiob

How many genes does the human organzism have?

20,000

how many pairs of chromosmes do humans have?

23

what is in each pair of chromosomes

one of the chromosmes in each paur is from you rmom and the other form your dad

What is true about both of the chromosomes in each paur

they have a code for identicla chracteristics but the chromosomes themsleve smight not be identical

What are different forms of a gene callded

alleles

wat can alleles be?

dominant or recessive

when does arecceisve allele devellop

if the allele is present in both chromosomes in the pair

when does a dominant allele devellop

at least one of the chromosomes in the pair contains it

genotype

teh complete genetic sequence of alleles in an organisms DNA

Phenotype

the set of traits that actually manifest in a person’s body, appearence, or behavior

What does phenotype comprise of

observable characteristics like eye color, height, outgoing personality, vulnerbaility to depression and unobservable chracteristics like blood type, immune system, etc. as well as behavior

how many apporaches are there to investigate genetic heratability

2

wata re the 2 ways?

genetic relatedness and molecular genetics

what does genetic relatdness involve?

comaring ppl with similar genotypes to ppl with less similar genotypes

wat is the idea behind genetic relatdness ?

ppl who have more similar genotypes are also more similar in terms of depression, then depression is genetiucally inherited (note this approach is not limited to depression)

Concordance Rate

the probability that one person in the pair has a trait if the other person has it

give an example of a concordance rate

if one twin had depression so does the other or if one twin doesnt have depression so doesnt the other

an example of disconcordant

if one twin has depression but the other doesnt

Twin studies

involves analyszing the differences in concordance rates between mono and dizygotic twins

monozygotic twins

devlop from same egg, so they share 100% of genotype

dizygotic twins

are born at the same time, but develop from seperate eggs so they share 50% of genotype on average just like regular siblings

Kendler et al (2006) what did it do

caonduct the sewdish national twin study of major depression

what was the aim of kendler et al

to compare genetic effect on MDD first in males and females and second across different generations

How did Kedler et al. assess depression and on how many twins?

42,000 twins by DSM-5 criteria in a computer-assited telephone interview

How did kedler et al. find the twins

in Swedish twin registry

What were the results of kedler et al

herataibility of MDD was way higher in women (42%) than men (29%), no evidence was found that genetic heratability of depression is different across different generations

How was the ability to do molecular genetics approach possible

with the devlopment of methods of DNA mapping and tech that allows us to create a full description of a person’s genes and their variants

what is one advantage and disadvantage of the tech used to do molecular genetics

tech is not cheap to use in research but it allows researchers to pinpoint specific genes that may be responsible for specific behaviors or symptoms

what is a opular bioliglcal eplanion for mental disorders

menal idsorders are caused by disruptions in the process of neurotransmission

give an exmaple of a disruption in the process of neurotransmission

an imbalnce of a certain neurotransmitter in the brain (too much or too little)

what is the nervous system

a system of neursons, the nerve cells

what does a neuron consist of

the body (soma), dendrites, and the axon

what are dendrites and the axon

filamnets that extrude from the soma

how many dendrites and axons are there

multiple dendrites but only one,single axon

what is the function of dendrites and soma

ti receive singals from other neurons

what is the funciton of the axon

to transmit signals onwards

what happens when the axon of one neuron appraoches a dendrite or soma of another neuron

a synapse is formed

what is another word for synapse

synaptic gap

what does a synapse do

ist a structure that connects 2 neurons

On average gow many connections does one neuron have with other neurons

15,000

The nature of info transmission in the nervous system is what?

partly electrical and partly chemical

Every neuron has a certain threshold of what?

excitation received from the other neurons

what would happen if the sum excitation exceeds this threshold

the neuron fires,

what is teh brief pulse called

action potential

describe what happens when the neuron fires

basically it genrates a breif pulse called an action potential tha trvaels along the axon to other neurons, passing the excitation furhter and the pulse akak aciton potenial reaches the end of the axon and there at the synaptic gap the mechansims of transmission becomes chemcial

when does the mechansims of tranmission becoem chemcical

when the action potnetial reaches the end of the axon and at the synaptic gap

what happens when the aciton potential reaches the end of the axon

a neurtransmitter is released from the axon terminal into the synaptic gap

what are neurtrasmitters

chemical messengers

what happens to neurotransmitters

they r constably synthesized in the neuron and moved to the axon terminal to be stored there

a released neurotransmitter is avilable in the synptic gap for how long?

for a short period of time

what happens to the released neurotransmitter during that period of time

it may be detsoryed aka meyabo.ized, pulled back into the pre-synaptic axon terminal thru reuptake, or reach the post-synaptic meebrane and bind to one of the receptors on its surface

if the neurotranmsiter binds to a receptor in the post-synaptic membrane what will happen

changes the membrane potential and contributes to activating an electric pulse in the post-synaptic neuron here the transmission mechanism become electrical again

what are SSRI’S

a class of drugs also known as selective serotonin reuptake inhibitor

wat do ssri’s do

they slectively inhibit/block the reuptake of the neurotransmitter serotonin from the synaptic gap, which increases the concentration of serotonin in the synapse, SSR,s have been shown to be effective against depression

what is the most widley discussed neurotransmitter in the context of dpression studies

serotonin

how old is the serotonin hypothesis of clinical depression

60 years old

the study of neurotransmitters as factors in developing a mental disorder is closely related to what?

treatment

What makes the research in this area challenging?

the complexity