biological psychology 1 Flashcards
What is heritability?
How much of the differences between individuals can be explained by their DNA.
What is included in a Punnett square?
Two parents, dominant/recessive genes, and the possible ratio for genotype/phenotype.
What is an allele?
Alternate forms of a gene that can alter genotypes/phenotypes.
How does variability happen?
When errors in DNA replication occur, affecting certain genes.
What are Turkenheimer’s Laws of behavioural genetics?
- All human behaviour traits are heritable.
- The effect of being raised in the same family is smaller than the effect of genes.
- A substantial portion of variance is not attributable to either genes or shared family environment.
- Most complex traits are shaped by many genes of small effect.
What is DNA?
It is a polymer made of nucleotide chains that form a double helix.
What are the nucleotide base pairs?
Adenine and Thymine, Guanine and Cytosine.
What is genetic inheritance?
A gene that is passed down from a parent to a child.
What did Seymore Kety’s adoption studies reveal about biology’s effect on behaviour?
It revealed that biological factors, like genes, play a role in disorders (including schizophrenia); environmental factors also play a role.
What are epigenetics?
The study of changes in gene function that are mitotically and/or meiotically heritable and do not entail a change in the sequence of DNA.
What are 2 epigenetic mechanisms, and how do they work?
- Histone remodelling: involves modifications to histone proteins which can increase or decrease gene expression.
- DNA methylation: involves the attachment of a methyl group to DNA which usually reduces the expression of adjacent genes.
How did the Dutch Hunger Winter (1944 - ‘45) affect individuals in early/mid/late periods of gestation?
- Early: glucose intolerance, hyperlipidaemia, altered blood coagulation, obesity (only women), stress sensitivity, coronary heart disease, breast cancer.
- Mid: glucose intolerance, microalbuminuria, obstructive airway disease.
- Late: glucose intolerance.
What were the trans-generational inheritance effects of the Dutch Hunger Winter?
Malnourishment in early gestation led to a normal weighing child, and their children were then born at an increased birth weight. On the other hand, malnourishment in late gestation led to a smaller weighing child, and their children were then born at a normal weight.
How were the effects of DNA methylation translated into animals?
Cooney, Dave, and Wolff, (2002) discovered that a methylated mouse was darker in fur and smaller weighing than the non-methylated mouse.
How were the effects of DNA methylation translated into animals?
Cooney, Dave, and Wolff, (2002) discovered that a malnourished mouse was darker in fur and smaller weighing than the nourished mouse.
What is the difference between endocrine and exocrine glands?
Endocrine glands and ductless and go straight to the circulator system - they are often organs with primary functions of hormone release. Exocrine glands are duct-based, like sweat glands.
Which hormones which have sex-related functions are secreted by the anterior pituitary?
It secretes testosterone, oestrogen, and cortisol.
Which hormones which have sex-related functions are secreted by the posterior pituitary?
It secretes oxytocin and vasopressin.
What are included in Classes of hormone I?
Amino acid derivatives like adrenaline, and peptides like prolactin, oxytocin, ACTH etc.
What is included in Classes of hormone II?
Steroids like testosterone, estradiol, progesterone etc.
What is the SRY gene?
It is a protein that is involved in male-typical sex development that is found in the Y chromosome.
How does the SRY gene affect the gonads?
Expression of the SRY gene leads to a size increase of the XY gonad, more than the XX gonad.
What is the main difference between steroid hormones and amino acid derivatives/peptides?
Steroids are sex hormones, while amino acid derivatives and peptides are not.
What is Androgenic Insensitivity syndrome?
It renders the androgen receptors unresponsive. A genetic male’s (XY) testes release testosterone but the body does not respond and develops as a female.
What is Congenital Adrenal Hyperplasia?
It is a deficit in the release of cortisol. A genetic female (XX) has an excessive release of androgens (hyperandrogenism) which has major and uncertain effects on sexual development.
What is 5α-Reductase 2 deficiency?
When a genetic male (XY) has 5α-Reductase 2 they convert T into DHT, which drives primary male sexual development. The body develops as a female but male secondary sexual characteristics emerge during puberty.
What are the differences in the brain between males and females?
- Various differences in size (overall and structures).
- Most differences are small, varying, and overlap across males and females.
- Sexual differentiation is different across structures.
What are the differences in behaviours between males and females?
- Many differences are due to pre-natal testosterone.
- Females with Congenital Adrenal Hyperplasia (who were exposed to pre-natal T) exhibit typical male behaviour.
- There are large differences in neurological and psychiatric diseases (multiple sclerosis affects more females than males, and vice versa are dyslexia, according to a study).
What are the differences in illnesses between males and females?
- Females experience higher rates of autoimmune/inflammatory diseases than males.
- Males experience higher levels of cancer and infections.
- Evidence suggests that females have a stronger and more responsive immune system, and therefore have less infections; this can lead to hyperactivity and cause autoimmune diseases.
