Genetics Review

Who is the “Father of Genetics”? Gregor Mendel What organism did Mendel use to study genetics? Pea Plants

Transmission of characteristics from parents to offspring is called ___________________. _____________ is the study of how characteristics are passed on from one generation to the next. heredity Genetics

__________________ = An allele that IS MASKED BY the presence of another allele Recessive The appearance of an organism is its _____________ phenotype

Another name for heterozygous hybrid The diagram at the right is called a _____________ Punnett square

__________________ = An allele that MASKS the presence of another allele Dominant A recessive gene is represented by a _________________ letter. lower case

_______________ are different gene choices for a trait. Alleles

A dominant gene is represented by a ____________ letter. (usually the first letter of the trait) capital When both alleles in the pair are the SAME the organism is ______________ Homozygous or purebred

When both alleles in the pair are DIFFERENT the organism is _________________ Heterozygous or hybrid monohybrid A cross that involves only 1 trait is called a ____________ cross.

Homozygous (HO) or Heterozygous (HE)? TT ____ Yy ____ Hh ____ Mm ____ Ee ____ kk ____ BB ____ ZZ ____ HO HE HO HE

Determine the Phenotype: Pink flowers are dominant to red flowers PP _____________ Pp _____________ pp _____________ Brown eyes are dominant to green eyes BB ____________ Bb ____________ bb ____________ Pink Red Brown Green Brown

For each phenotype, list the genotype: Straight hair is dominant to curly. ____________ straight ____________ straight ____________ curly Square heads are dominant to round heads. ____________ square ____________ square ____________ round SS Ss ss SS Ss ss

In guinea pigs, black fur (B) is dominant over brown fur (b). If a black Guinea pig is crossed with a brown Guinea pig and the litter contains a brown baby, the genotype of the black parent is probably BBBb bb Bb; Must have one B to be black must have one b to pass on to baby

T = Tall t = short The genotype of the offspring from the cross at the right is _________. Their phenotype is _________. Tt tall

The parents in this cross are _____________ Homozygous Heterozygous Heterozygous If G is dominant for green pods and g is recessive for yellow pods, what percentage of the offspring will have green pods? _______% 75 GGGg gg G g G g

What are the possible phenotypes of their offspring? (% and color) Red throats (R) are dominant over white (r) throats in Goonie birds. Make a cross between a PURE RECESSIVE and a HETEROZYGOUS Goonie bird. 50% red throats 50% white throats Rr rr R r r

What are the possible phenotypes of their offspring? (% and color) Black eyes (B) are dominant over red eyes (b) in rats. Make a cross between two HETEROZYGOUS rats. 75 % black eyes 25% red eyes B b B b BB Bb Bb bb

The parents in this cross are _____________ Homozygous Heterozygous Homozygous If W is dominant for long wings and w is recessive for short wings, what percentage of these offspring will have short wings? _______% 0% only ww makes it short

What is the probability the offspring will have straight tails? In Reebops curly tails (T) are dominant over straight tails (t). Make a cross between a HOMOZYGOUS DOMINANT and a HOMOZYGOUS RECESSIVE Reebop. 0% All will be Curly tailed (Tt) Tt Tt Tt T T t

What will the offspring be like? (% and color) Purple (P)is the dominant color for monsters. Yellow is recessive (p). Make a cross between a HOMOZYGOUS purple and a yellow monster. 100% purple Pp P P p