Chapter 4 Flashcards
What is it when you have the same genes on your two copies of some chromosome?
Homozygous
If you have an unmatched pair of genes you are _ for that gene
Heterozygous
A recessive gene shows its effects only in what condition?
If the gene is homozygous
What genes are present in both sexes but mainly active in one sex? (ex - chest hair on men or breast size on women)
Sex-limited genes
What is a mutation?
A heritable change in a DNA molecule
A heritable change in a DNA molecule
Monozygotic; Dizygotic
The genetic inability to metabolize phenylalanine is known as _
Phenylketonuria
How does a gene influence behavior?
By producing a protein that interacts with the rest of the body chemistry & environment
_ is a change over generations in the frequencies of various genes in a population
Evolution
An action that benefits someone other than the actor is called a/an _
Altruistic behavior
What does a microdeletion remove?
Part of a chromosome
: How does epigenetic change differ from a mutation?
An epigenetic change alters gene activity without replacing it
How does adding a methyl or acetyl group to a histone alter gene activity?
Methyl turns genes off, acetyl accelerates gene activation
What is responsible for evolutionary change in a species?
People with certain genes reproduce more often than average
_ Is the production of new cells
Proliferation
What is the term for the formation of synapses?
Synaptogenesis
The process by which glia produce insulating fatty sheaths that speed transmission in many vertebrate axons is known as _
Myelination
When one of the Sympathetic system’s neurons forms a synapse onto a muscle, that muscle delivers a protein called _ that promotes survival & growth of the axon
Nerve growth factor
A chemical that promotes the survival & activity of a neuron is a _
Neurotrophin
In lab rats, an enriched environment promotes growth in axons & dendrites - Why is this?
Animals are more active in an enriched environment & this exercise promotes growth of axons & dendrites
Musicians cramp is also known as _
Focal hand dystonia
True or false: In old age, many neurons lose some of their synapses & the remaining synapses change slower than before in response to experiences
True
True or false: In early brain development, the muscle movements occur before sensory systems develop
True
Which areas do new neurons develop in during adulthood?
Hippocampus & basil ganglia
