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