Question

1. in pea plants, green pods are dominant over yellow pods. cross a plant with yellow pods with a plant that is heterozygous for green pods.

1. in pea plants, flowers that bud on the top of the plant (terminal position) is dominant, and flowers that bud on the sides of the plant (axial position) is recessive. cross a heterozygous terminal flowering plant with a homozygous terminal flowering plant.

1. in pea plants, the seed coat can be green or white. green is dominant over white. construct your own punnett square that involves one heterozygous parent in which 50% of the offspring can be predicted to have green seed coats.

1. a pea plant that is pure for purple flowers mates with a pea plant that has white flowers. one of their offspring self - fertilizes and produces 100 offspring. how many would you predict turn out to have purple flowers and how many would you predict turn out to have white flowers?

1. of those offspring, 70 are white and 30 are purple. how is this different than your prediction? is this possible? why or why not?

Explanation:

Step1: Define alleles for Q6

Let $G$ = dominant green pod, $g$ = recessive yellow pod.
Yellow plant: $gg$; Heterozygous green plant: $Gg$

Step2: Set up Punnett Square for Q6

	$G$	$g$
$g$	$Gg$	$gg$

Genotype ratio: $\frac{1}{2}Gg$, $\frac{1}{2}gg$; Phenotype ratio: 1 green : 1 yellow

Step3: Define alleles for Q7

Let $T$ = dominant terminal flower, $t$ = recessive axial flower.
Heterozygous terminal: $Tt$; Homozygous terminal: $TT$

Step4: Set up Punnett Square for Q7

	$T$	$t$
$T$	$TT$	$Tt$

Genotype ratio: $\frac{1}{2}TT$, $\frac{1}{2}Tt$; Phenotype ratio: 100% terminal flowers

Step5: Design cross for Q8

Let $S$ = dominant green seed coat, $s$ = recessive white seed coat.
Heterozygous parent: $Ss$; To get 50% green offspring, cross with homozygous recessive $ss$
Punnett Square:

	$S$	$s$
$s$	$Ss$	$ss$

Phenotype ratio: 50% green ($Ss$), 50% white ($ss$)

Step6: First cross for Q9

Let $P$ = dominant purple flower, $p$ = recessive white flower.
Pure purple: $PP$; White flower: $pp$
First cross offspring: all $Pp$ (purple)

Step7: Self-fertilize $Pp$ for Q9

Punnett Square for $Pp \times Pp$:

	$P$	$p$
$p$	$Pp$	$pp$

Phenotype ratio: $\frac{3}{4}$ purple, $\frac{1}{4}$ white. For 100 offspring:
Purple count: $100 \times \frac{3}{4} = 75$; White count: $100 \times \frac{1}{4} = 25$

Step8: Analyze Q10 deviation

Prediction: 75 purple, 25 white; Observed: 30 purple, 70 white. Observed has far more white flowers. This is possible because Punnett square ratios are statistical probabilities, not fixed outcomes. Random fertilization can cause real-world offspring counts to deviate from predicted ratios, especially with small sample sizes.

Answer:

1. Genotype ratio: 1 $Gg$ : 1 $gg$; Phenotype ratio: 1 green pod plant : 1 yellow pod plant
2. Genotype ratio: 1 $TT$ : 1 $Tt$; Phenotype ratio: 100% terminal flowering plants
3. Cross a heterozygous green seed coat plant ($Ss$) with a homozygous white seed coat plant ($ss$). Punnett square yields 50% green ($Ss$) and 50% white ($ss$) offspring.
4. 75 purple-flowered offspring, 25 white-flowered offspring
5. The observed count has far fewer purple flowers and far more white flowers than the predicted 75 purple/25 white. This is possible because Punnett square ratios are only statistical expectations, not guaranteed results. Random chance in fertilization can lead to deviations from predicted ratios, especially with a relatively small sample size of 100 offspring.