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5. Pedigree Drawing

To draw this pedigree, we follow three generations:
1. Generation I: Julie (Circle) and Jeff (Square) are connected by a horizontal line. A vertical line drops down to their child.
2. Generation II: Their daughter is Josephine (Circle). She connects to her husband, Joseph (Square). They have two sons: Jason (Square) and Joe (Square).
3. Generation III: Joe connects to his wife, Julia (Circle). They have three children: Shannon (Circle), and fraternal twin boys Mark and Alex (two Squares side-by-side).
4. Generation IV: Mark connects to his wife, Alison (Circle). They have two children: Ray (Square) and Scarlet (Circle).

*(Note: Since I cannot draw directly on your paper, use the description above to sketch the shapes and lines. Circles are females, Squares are males.)*

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A. Identify the Pedigree Charts

1. Is the following autosomal or X-linked? Is it dominant or recessive?

* Step 1: Dominant or Recessive?
Look at the parents at the top. Both the mother (circle) and father (square) are white (unaffected). However, they have children who are black (affected). When unaffected parents have an affected child, the trait must be recessive. The parents are "carriers" hiding the gene. If it were dominant, one of the parents would have to be affected to pass it on.

* Step 2: Autosomal or X-linked?
Look at who is affected. Only the males (squares) are affected in this family. In X-linked recessive traits, males are much more likely to be affected because they only have one X chromosome. If they inherit the bad gene on that single X, they show the trait. Females have two X chromosomes, so they usually need two copies of the bad gene to be affected. Because only males are showing the trait here, it is most likely X-linked.

Conclusion: It is X-linked Recessive.

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2. Is the following autosomal or X-linked? Is it dominant or recessive?

* Step 1: Dominant or Recessive?
Look at the pattern. The trait appears in every generation (it doesn't skip anyone). Also, look at the affected individuals—they all have at least one affected parent. For example, the affected female in the second generation has an affected mother. This "vertical" pattern where it never skips a generation suggests it is dominant.

* Step 2: Autosomal or X-linked?
Let's test if it could be X-linked Dominant. In X-linked dominant inheritance, an affected father passes his only X chromosome to *all* his daughters. Therefore, every daughter of an affected male must be affected.
Look at the bottom right of the chart. There is an affected male (black square) married to an unaffected female. They have a daughter who is unaffected (white circle). Because an affected father had an unaffected daughter, this cannot be X-linked. Therefore, it must be autosomal.

Conclusion: It is Autosomal Dominant.

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3. Is the following autosomal or X-linked? Is it dominant or recessive?

* Step 1: Dominant or Recessive?
Look at the very bottom generation. There is an affected father (black square) and an unaffected mother (white circle). They have both affected and unaffected children. This doesn't rule out anything yet.
Now look at the middle-left. An unaffected couple (white circle and white square) has an affected son. Wait, looking closer at the diagram provided in question 3... actually, let's look at the top right. Two unaffected parents have an affected daughter (black circle).
*Correction:* Looking at the specific chart for #3:
Top Right: Unaffected parents have an affected daughter. This proves it is Recessive (unaffected parents having an affected child).

* Step 2: Autosomal or X-linked?
We established it is recessive. Now, can it be X-linked recessive?
Rule for X-linked recessive: An affected female (daughter) must have an affected father. Why? Because she needs two bad X genes ($X^r X^r$). One comes from mom, one comes from dad. So dad must be $X^r Y$ (affected).
Look at the top right of chart #3 again. There is an affected daughter (black circle), but her father is unaffected (white square). This is impossible for X-linked recessive. Therefore, it must be Autosomal.

Conclusion: It is Autosomal Recessive.

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Final Answer:

5. Pedigree Structure:
* Gen 1: Julie (female) + Jeff (male)
* Gen 2: Josephine (female, daughter of Julie/Jeff) + Joseph (male) $\rightarrow$ Children: Jason (male), Joe (male)
* Gen 3: Joe (male) + Julia (female) $\rightarrow$ Children: Shannon (female), Mark & Alex (fraternal twin males)
* Gen 4: Mark (male) + Alison (female) $\rightarrow$ Children: Ray (male), Scarlet (female)

A. Pedigree Identification:

1. X-linked Recessive.
* *Reasoning:* It is recessive because unaffected parents have affected children. It is X-linked because only males are affected, which is characteristic of X-linked traits where males are hemizygous.

2. Autosomal Dominant.
* *Reasoning:* It is dominant because the trait appears in every generation and affected individuals have affected parents. It is autosomal because an affected father has an unaffected daughter (if it were X-linked dominant, all his daughters would be affected).

3. Autosomal Recessive.
* *Reasoning:* It is recessive because unaffected parents have an affected child (specifically the top-right family unit). It is autosomal because an affected daughter has an unaffected father (if it were X-linked recessive, her father would have to be affected).