Chapter 4 Flashcards
all organisms inherit genetic information specifying their ____ and ____ from their parents
structure and function
all cells arise from preexisting cells, so the genetic material must be replicated and passed from parent to progency each ______
cell division
The classical principles of genetic were deduced by Gregor Mendel in 1865, from his experiment with _________
pea plants
Mendel studied well-defined traits, such as _____, and could predict _____ by assuming each trait is determined by a pair of inherited factors, now called ___________-
he studied pea plants
well defined traits such as seed color
he predicted patterns of inheritance
inheritable factors called genes
one copy _____ specifying each trait is inherited from each parent
allele
His progeny (f generation) were hybrids that had yellow seeds yellow ____ and green _____
yellow dominant
and green recessive
define genotype
is the genetic makeup of an individual
define phenotype
it is the resulting physical appearance. the genotype of the F1 generation is Yy the phenotype is yellow.
A dominant: recessive = (whats the ratio?)
3:1
most cells of plants and animals are ____: containing two copies of each chromosome
diploid
define meiosis
only one member of each chromosome pair is transmitted to the progency cell
the sperm and egg are _____: containing one copy of each chromosome
haploid
at fertilization, two ___ cells are combined to make a new _____ cell
haploid
diploid
The fundamentals of mutation, genetic linkage, and relationships between genes and chromosomes were largely established by experiments with the ________
fluid fly, drosophila melangoaster
in the early 1900s ___________________ were observed in the drosophila (fruit fly) that affected characters such as eye color and wing shape
mutations (genetic alterations)
breeding experiments showed that some of these genes are inherited independently of each other. This suggests that the genes are ______ chromosomes that segregate independently during meiosis
diffwerent chromosomes
genes located on the ___ chromosome are inherited together and are said to be linked
same chromosome
genes located on the ___ chromosome are inherited together and are said to be linked
same chromosome
DNA is a ______
double helix
the backbones of DNA is made out of ____ whiles the outside is made of ____ and the inside is hydrogen bonds formed between purines and pyrimidines on opposite chains. The base paring is very specific: A always Pairs with T and G with C
backbones= sugar, phosphate
outside=bases
the DNA helix turns every ___ nm. the distance between adjacent bases is ______nm
3.4 nm… distance between adjacent bases is 0.34 nm
semiconservative replication is?
one strand of parental DNA is conserved in each progeny DNA molecule
in the presence of DNA to act as a template ______ directed the incorporation of nucleotides into a complementary DNA molecule
DNA polymerase
although DNA appeared to specify the order of amino acids in proteins, it did not necessarily follow that DNA itself directs protein synthesis. DNA is located in the nucleus of eukaryotic cells, but protein synthesis occurs in the ___________
cytoplasm