1.2 Genetics And Behaviour Flashcards
Mendelian genetics. ____ demonstrated that inheritance occurs through genes, units of heredity that maintain their structural identity from one generation to another.
Mendel
Everything you do depends on both your ____ and your ____.
genes, environment
As a rule, genes come in pairs because they are aligned along ____ (strands of genes) that also come in pairs.
chromosomes
Classically, a gene has been defined as a portion of a chromosome, which is composed of a double-stranded molecule ____ ____ (DNA).
deoxyribonucleic acid
Sometimes several genes ____ on a stretch of chromosome. Sometimes a genetic outcome depends on parts of two or more chromosomes.
overlap
A strand of DNA serves as a template (model) for the synthesis of ____ ____ (RNA) molecules, a single strand chemical.
ribonucleic acid
One type of RNA molecule – messenger RNA – serves as a template for the synthesis of ____ molecules.
protein
DNA contains four bases – ____, ____, ____, and ____ – in any order.
adenine, guanine, cytosine, and thymine
The order of DNA bases determines the order of corresponding bases along an RNA molecule – ____, ____, ____, and ____.
adenine, guanine, cytosine, and uracil
The order of bases along an RNA molecule in turn determines the order of ____ ____ that compose a protein.
amino acids
Some proteins form part of the structure of the body. Others serve as ____, biological catalysts that regulate chemical reactions in the body.
enzymes
Anyone with an identical pair of genes on the two chromosomes is ____ for that gene. An individual with an unmatched pair of genes is ____ for that gene.
homozygous, heterozygous
Genes are dominant, recessive, or ____.
intermediate
A ____ gene shows a strong effect in either the homozygous or heterozygous condition.
dominant
A ____ gene shows its effects only in the homozygous condition.
recessive
The genes on the sex chromosomes (designated X and Y) are known as ___-____ genes.
sex-linked
All other chromosomes are ____ chromosomes, and their genes are known as autosomal genes.
autosomal
Distinct from sex-linked genes are the ___-____ genes, which are present in both sexes, generally on autosomal chromosomes, but active mainly in one sex.
sex-limited
Examples of sex-limited genes include the genes that control the amount of chest hair in men or breast size in women. Both sexes have those genes, but ___ ____ activate them and one sex or the other.
sex hormones
Genes change in several ways. One way is by ____, a heritable change in a DNA molecule.
mutation
Another kind of mutation is a ____ or ____. During the process of reproduction, part of a chromosome that should appear once may instead appear twice or not at all.
duplication or deletion
The field of ____ deals with changes in gene expression without modification of the DNA sequence.
epigenetics
Changes in gene expression are also central to learning and memory and to brain changes resulting from ____ ____.
drug addiction
Proteins call ____ bind DNA into a shape that is more like a string wound around a ball.
histones