Structure and Function Test Flashcards
chromosomes
threadlike structure of nucleic acids and proteins found in the nucleus of most living organisms; carries genetic info
genes
unit of heredity transferred from parents to an offspring; determines characteristics
human genome
23 chromosome pairs; 3 billion DNA base pairs; 24 distinct chromosomes
bases or nucleotides
adenine, guanine, cytosine, thymine, deoxyribose
purines
colorless crystalline compound w basic properties
guanine
one of the four bases of nucleic acids; pairs w cytosine
adenine
one of the bases of nucleic acids; pairs w thymine
pyrimidines
colorless crystalline compound w basic properties
cytosine
one of the bases of nucleic acids; pairs w guanine
thymine
one of the bases of nucleic acids; pairs w adenine
double helix
shape of DNA
replication
duplicating an exact copy of DNA strands
law of independent assortment
alleles of two or more different genes get sorted into gametes independently of one another
linked genes
genes that are likely to be inherited together because they are physically close to one another
recombination
rearrangement of genetic material
crossing over
exchange of genes
genetic engineering
modification of characteristics of an organism by manipulating its genetic material
sex chromosomes
xx for females and xy for male
autosomes
any chromosome that is not a sex chromosome
sex-linked traits
parents carry genetic material in their sex chromosomes to pass on to their offspring
sex-limited traits
characters expressed physically in one sex of a species
sex-influenced traits
expressed in both sexes to different degrees
genome
complete set of genes or genetic material presenting a cell or organism
karyotype
pictures of chromosomes
nondisjunction
failure of chromosomes to separate during a cell division
