Genetics Even More Genetics Stuff Yet More Genetics Stuff. Still, Yet, Even More Genetics Stuff The last of the Genetics Stuff 100 100 100 100 100 200 200 200 200 200 300 300 300 300 300 400 400 400 400 400 500 500 500 500 500

What do skin color, hair color, and eye color have in common?

They are multiple genes traits (they’re determined by MULTIPLE genes).

How are mitosis and meiosis similar? How are they different?

Body cells (occurs in all organisms) Mitosis Asexual Body cells (occurs in all organisms) Prophase, metaphase, anaphase, telophase Results in two daughter cells. New cells have normal number of chromosomes (2N-diploid) New cells fully functional Meiosis Sexual Gametes (animals and plants) Prophase, metaphase, anaphase, telophase…twice! Results in four daughter cells. New cells w/ ½ normal number of chromosomes (N-haploid). New cells need to combine with another gamete before they’re fully functional.

Using bacteria to produce human insulin is an example of______?

Genetic Engineering.

Colorblindness is a sex-linked recessive trait Colorblindness is a sex-linked recessive trait. What do the genotypes of each parent of a colorblind child have? Why do males have a greater chance of being colorblind?

At least one recessive allele. The allele is linked to the X chromosome. Males are XY. If a male gets the recessive allele there is no chance of getting a dominant allele that will mask it.

What happens to cause Down syndrome?

One of the chromosome fails to separate properly during meiosis (meiotic disjunction). This results in one extra chromosome in pair #21. This is known as TRISOMY 21.

What causes genetic disorders such as sickle-cell anemia?

Mutations.

What is a pedigree?

A chart that tracks the occurrence of a trait in a particular family.

What is hemophilia?

A genetic disorder that prevents blood from clotting the way it should A genetic disorder that prevents blood from clotting the way it should. Sex linked disorder

What is cystic fibrosis?

An autosomal recessive genetic disorder that causes a protein malformation. It results in thick mucus in the lining of the lungs and intestines and frequent (and resistant) bacterial infections.

What is the term for a picture of the chromosomes in a cell?

A Karyotype.

What is the difference between incomplete dominance and co-dominance?

Incomplete Dominance: R=Red flowers, r=white flowers Rr=pink flowers rather than red. Co-dominance: R=Red flowers, r=white flowers Rr=flowers with patches of red and patches of white.

What is the difference between inbreeding and hybridization?

Inbreeding: crossing two individuals with identical or similar alleles to produce specific traits. This can increase the chance of inheriting genetic disorders Hybridization: crossing two individuals with different traits, so offspring might get the best traits of both. Used in agriculture.

What is cloning?

A procedure that produces an organism that is genetically identical to the parent.

Can environment affect phenotype? Explain.

YES! You may be genetically predisposed to be 6’4” tall, but without the proper nutrition…ain’t gonna happen!

What genetic disorder is characterized by abnormally formed hemoglobin?

Sickle-Cell Anemia! Which causes the “sickle” shape!

What does the notation Rr mean to a geneticist?

One dominant and one recessive allele One dominant and one recessive allele. This genotype is also known as heterozygous or hybrid.

What do homozygous and heterozygous mean?

Homozygous means two of the same alleles Homozygous means two of the same alleles. Heterozygous means one recessive and one dominant allele.

What is the difference between a genotype and a phenotype?

Phenotype = the physical (sometimes) visible traits of an organism (example: blue eyes, type AB blood). Genotype = the genetic make-up of an organism…its chromosomes (example: Bb, BB, bb).

Explain the relationship among DNA, chromatin, chromosomes, genes, alleles, and traits.

DNA is the molecule that codes for heredity DNA is the molecule that codes for heredity. Normally it is in the form of chromatin, but during cell division it forms structures called chromosomes. A gene is a specific part of a chromosome that is responsible for a certain trait. Alleles are the various forms of expression for a given trait.

If a heterozygous parent is crossed with another heterozygous parent, what is the probability that the offspring will be homozygous recessive?

1:4 or 25%

What is a purebred?

Homozygous dominant or Homozygous recessive)

What is the chromosome theory of inheritance?

Genes are passed from parents to offspring on chromosomes.

What is a pedigree? What do the various shapes and shading on a pedigree represent?

A pedigree is a chart that shows how traits are passed from one generation to another. Open Circle = Normal Female Half-shaded Circle=Carrier Female Shaded Circle=Affected Female Open Square = Normal Male Half-shaded Square =Carrier Male Shaded Square =Affected Male

If you have the A and B alleles for blood type, what type blood do you have?

AB

Are males XX or XY?

XY