Lecture 1 Flashcards
Does laughter have a biological basis?
Yes, this is known via genetics and evolution.
Scientists have found a specific allele and have found pre-existing traits of laughter in ancestral apes.
Is there such thing as mixed inheritance?
No, we are not a blend of our parents, we just inherit traits depending on whether they’re dominant or recessive.
What did Mendel discover?
He discovered that genes are units of heredity that maintain structure through generations. He also found that genes are part of chromosomes.
What is a genotype?
What is a phenotype?
An internal genetic code
An outward manifestation
What are alleles?
Do genes come in pairs?
Explain
Different versions of the same gene.
Yes, they’re either homozygous or heterozygous and they can be dominant or recessive.
Give an example of genetics affecting behaviour
The PTC gene can cause food aversion. If you can taste PTC then you have a dominant allele. If one of your parents are homozygous dominant and the other recessive then you will definitely taste PTC. If they’re both heterozygous then there’s a 75% chance you’ll taste PTC.
How many sex chromosomes do you have?
You have 1 pair of sex chromosomes. Either XX (female) or XY (male).
Where are sex linked genes located?
Explain
What does this mean?
On the X chromosome.
This is because the X chromosome is much larger and more likely to carry genetic information. Therefore, men are more likely to get recessive disorders as the gene only needs to be present on one chromosome. This is the case with red-green colour deficiency.
List 3 behaviours that seem to have high heritability
How can you find this out?
Name a problem with this method
Neuroticism, alcoholism and social attitudes.
Twin studies and adoption studies
You can’t prove 100% heritability cause twins have pre-natal influences which have been found to have genetic effects.
What does fitness mean in terms of evolution?
It means that one has more successful traits and is therefore more likely to survive and reproduce. If traits spread through a population then speciation can occur but this can’t be caused by just one trait.
What are the four types of evidence for evolution?
Fossil record, similarities between related species, artificial selection and geographical distribution. For example related species (marsupials) on the same island.
What is an analogy?
When unrelated species have very similar phenotypes due to their environmental niches.
List 4 common misunderstandings of evolution?
Lamarckian inheritance meaning changes occur within a lifetime.
Evolution is only a forward movement.
Humans evolved from monkeys.
Humans have stopped evolving.
True or false
Evolution looks for biological explanations for behaviour
Yes it does but it must also look for functional explanations. Why did it evolve. For example, language.
Is there phylogenetic continuity between humans and chimps?
Yes, when traced back to our last common ancestor, comparisons have shown similarities in vocalisations.
