Honors Biology- Chapter 15
What is a sex-linked trait? Give examples
- Carried on the X or Y chromosome - webbed toes, hypertrichosis, color blindness
When do symptoms for sickle cell start to show?
4-6 months
What are karyotypes? How are they arranged?
A micrograph of the full diploid set of chromosomes an organism possesses; large to small orcer
Explain how color blindness is inherited. Why is it more common in men?
Carried on the X chromosome. Men only need one recessive allele for the trait to show
What do karyotypes show?
Chromosomal disorders like Down's syndrome and cancer
Is Huntington's disease dominant or recessive?
Dominant
Name three disorders that can be determined by karyotype
Down's, Edward's, Turners, Klinefelters, Super-female
Restriction enzyme
Enzyme that cuts DNA at a specific sequence of nucleotides
Nondisjunction
Error in meiosis in which homologous chromosomes fail to separate properly
What does a pedigree show? What does a half colored in circle or square show?
Family relationships and the passing of traits with families
When do symptoms for cystic fibrosis start to show?
First year of life
Is Huntington's disease a point or a frameshift mutation?
Frameshift
Is cystic fibrosis a point or a frameshift mutation?
Frameshift
How do restriction enzymes work?
From bacteria. Restriction enzymes cut both strands of DNA at a specific sequence depending on the R.E. chosen
When do symptoms for Huntington's disease start to show?
Middle age (35-45 yrs)
At what point in the cell cycle are chromosomes photographed for a karyotype?
Mitosis
Compare the human genome in size and number of genes to other species.
Not the largest, not the smallest; between chickens and grapes
Is sickle cell a point or a frameshift mutation?
Point
Gel electrophoresis
Procedure used to separate and analyze DNA fragments by placing a mixture of DNA fragments at one end of a porous gel and applying an electrical voltage to the gel
Is cystic fibrosis dominant or recessive?
Recessive
What is an SNP and why is it important?
Single nucleotide polymorphism Differences in our DNA code that can cause diseases or specific traits
In gel electrophoresis, which particles move faster? Smaller DNA fragments or larger ones? What makes them move?
Smaller; electricity
What sex chromosomes are present in a normal male? Female?
XY, XX
Pedigree
chart that shows the presence or absence of a trait according to the relationships within a family across several generations
Autosome
chromosome that is not a sex chromosome; also called autosomal chromosome
What does any genome analysis begin with?
chromosomes
Genome
entire set of genetic information that an organism carries in its DNA
Sex linked gene
gene located on a sex chromosome
Karyotype
micrograph of the complete diploid set of chromosomes grouped together in pairs, arranged in order of decreasing size
Sex chromosome
one of two chromosomes that determines an individual's sex
Genomic imprinting
process in which epigenetic marks affect gene expression by altering chromatin structure
Is sickle cell dominant or recessive?
recessive