The Genetic Basis of Variability, Sample of Genetic Conditions Linked with Behaviour, Cognition

Question 1

Nature

Answer 1

Influences from our genetic endowment (what you are born with/genetic influences)

Question 2

Nurture

Answer 2

Environmental influences that shape us

Question 3

Theory of natural selection

Answer 3

• Reproductive success
  
  • Biological evolution (genes change)
  • Adaptive (helps with survival) vs. deleterious traits (leads to death)

Question 4

Two components of natural selection

Answer 4

Variation

Competition

Question 5

Variation

Answer 5

Genotypes and phenotypes

Question 6

Competition

Answer 6

For limited resources

Question 7

Genetics

Answer 7

study of genes, how they are passed on and how they differ

Question 8

DNA

Answer 8

sugar base with phosphate and nucleotides

Question 9

Genes

Answer 9

small units of DNA that direct the synthesis of proteins and enzymes

Question 10

Genome

Answer 10

A total/complete set of genetic material

Question 11

Heredity

Answer 11

Sum of inherited traits and tendencies

Question 12

Alleles

Answer 12

Variations of a gene

1. Genotype
2. Phenotype

Question 13

Genotype

Answer 13

Organism’s genetic makeup and appearance of cells

Question 14

Phenotype

Answer 14

• Outward expression of an organism’s genotype
  
  • Observable traits and characteristics of an organism
  • Not necessarily genetic

Question 15

Dominant traits

Answer 15

• If present = phenotype because they suppress recessive traits
  
  • Observed phenotype when the individual is heterozygous
  • Phenotype will always be represented when that allele for that gene is present

Question 16

Recessive trait

Answer 16

• Masked by a dominant allele when a dominant and recessive allele are present for the same gene
  
  • Will only present itself when 2 recessive alleles for a trait are present

Question 17

Proteins

Answer 17

strings of AAs, 3 nucleotides (codon) = 1 AA

Question 18

Enzymes

Answer 18

govern processes, control cell structure and function

Question 19

Chromosomes

Answer 19

threadlike; in nuclei of cell, contains genes

Question 20

Meiosis

Answer 20

ell division; new sperm and ova, randomly rearranged, contains 23 indie chromosomes when done (1/2 those found in other cells)

Question 21

Mutation

Answer 21

Accidental alterations in a single gene (environmental or spontaneous)

Question 22

Hayflick number

Answer 22

• Each cell can go through a limited number of divisions before death (~50 in humans)
  
  • Number of times a normal human cell population will divide until cell division stops

Question 23

Telomeres

Answer 23

• Every reproduction of a cell, you lose a part of the telomere (which is at the end), eventually you’ll lose DNA when the telomeres run out

  * Can monitor your ageing  * Variations across species  * Heritability

Question 24

Down syndrome

Answer 24

Dr. John Down

Chromosomal aberration
Trisomy 21
Mental retardation
Alzheimer’s Disease

Question 25

Chromosomal aberration

Answer 25

Rearrangement of genes with chromosomes or change in total number of chromosomes

Question 26

Trisomy 21

Answer 26

3 chromosomes instead of 2

Question 27

Physical characteristics

Answer 27

Facial

Question 28

Mental retardation

Answer 28

2 standard deviations below the mean

Question 29

Alzheimer’s Disease

Answer 29

• Much earlier (30-40 years old)
  
  • Is chromosome 21 related to Alzheimer’s?

Likelihood of a child born with it increases with the age of the mother

Question 30

Huntington’s disease

Answer 30

• Dr. George Huntington
  
  • Impairment mapped to Chromosome 4
    • DNA base repeat (CAG on chromosome 4)
      • More times repeated = more severe damage to basil ganglia (it dies)
  • Progressive neurodegenerative disorder
    • Gets worse and worse
    • Damages brain cells
  • Onset around 40, time course 10-15 years
    • Mothers rarely know they have it before giving birth

Question 31

Chorea

Answer 31

• Abnormal involuntary movement disorder
  
  • Quick movements of feet or hands are comparable to dancing
  • Brief, semi-directed, irregular movements that are not repetitive or rhythmic
  • Appear to flow from one muscle to the next

Question 32

Athetosis

Answer 32

Involuntary convoluted, writhing movements of the fingers, arms, legs, and neck

Question 33

Behavioural changes of Huntington’s

Answer 33

Depression and mood swings

Question 34

Phenylketonuria (PKU)

Answer 34

• Autosomal recessive disorder

  * If blood levels of phenylalanine rise = severe brain damage  * Inability to convert phenylalanine (found in food and artificial sweetener) to tyrosine  * Build up of phenylalanine causes impaired brain development, mental retardation and seizures  * Manageable if caught early; just stay away from it