Unit 6 GB JAG Review

Can you compare/contrast somatic cells and gametes?

Diploid (two copies of each chromosome) Humans 46 Somatic Cell Gamete Body cells muscle, liver, skin Diploid (two copies of each chromosome) Humans 46 Cells made from meiosis Egg and sperm Haploid (one copy of each chromosome) Humans 23

Do you know what a karyotype is and how its used to determine the sex of an organism?

Which are AUTOSOMES? Which are SEX CHROMOSOMES?

Do you know the difference between sister chromatids and homologous chromosomes?

Can you describe the movement of chromosomes during meiosis?

Is this cell diploid or haploid?

Can you explain the alternation of haploid and diploid cells throughout a human life cycle?

Do you know Mendel’s conclusions within the Law of Segregation?

Traits are inherited as discrete units. Organims inherit two copies of each gene, one from each parent. The two copies segregate during gamete formation.

Do you know vocabulary?

Gene: piece of DNA on a specific location of a chromosome Allele: different forms of a gene (B or b) Homozygous: two of the same alleles (BB or bb) Heterozygous: two different alleles (Bb) Genotype: genetic makeup (combination of alleles) Phenotype: physical characteristic that is expressed Dominant allele: allele that is expressed Recessive allele: allele that is “hidden” by a dominant allele

Can you perform a monohybrid cross and use it to make predictions of offspring?

Are the parents heterozygous or homozygous? What is the probability of having a child who is homozygous? Heterozygous? What is the probability of having a child with the dominant trait? Recessive trait?

Can you explain what a testcross is and when it would be used?

Cross between an organism with an unknown genotype and an organism with the recessive phenotype

Can you perform a dihybrid cross accurately?

Can you explain Mendel’s Law of Independent Assortment?

Allele pairs separate INDEPENDENTLY of each other during meiosis

Can you explain the difference in inheritance patterns of autosomal and sex-linked genes?

Autosomal: both males and females can be carriers Carrier: a heterozygote for a recessive disorder

Sex-linked: Only FEMALES can be carriers because it is located on X chromosome (#23 in humans) (males either have the disorder or do not have the disorder)

Can you determine the phenotype of offspring for codominant and incomplete dominant traits?

Codominance Both alleles will be completely expressed.

Incomplete Dominance The heterozygous phenotype is intermediate between the two homozygous phenotypes.

Can you perform a multiple allele cross to determine the blood type of offspring?

Proper Notation (with I’s): Letter Notation AB BB B

Can you explain how the environment can play a role in determining an organisms phenotype?

A person’s genotype may not change, but the texture, health, and color may be affected depending on environmental factors.

Do you know how to read a pedigree and use it to predict possible phenotypes and genotypes?

Can you determine the phenotype of III-3? How do you know? Males: Females: Shaded: have trait Can you determine the phenotype of III-3? How do you know?

Can you explain how females can carry sex-linked disorders and how they are identified by pedigrees?