Answer:
a. Heterozygous individuals may pass on their copy of the disease-causing allele to offspring.
Explanation:
Tay-Sachs, which is a recessive lethal disease ---- Let say the recessive lethal diseases is s
∴ it only results when an individual posses two copies of the diseases-causing allele i.e two copies of the disease will be ss.
Now, when two hetrozygous individuals crossed , it is obvious that each can pass on their copy of the disease-causing allele to the offspring.
Let show an illustration for the above statement.
Let the heterozygous individual be Ts, if Ts cross with another Ts;
we will have:
Ts × Ts
T s
T TT Ts
s Ts ss
the offspring are TT,Ts,Ts,ss
We can now see how the Heterozygous individuals pass on their copy of the disease-causing allele to the offspring (Ts).
The answer would be B. chromosome 21
The answer to your question is <span>chemical energy
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Mitochondria are found in all body cells.
Answer:
The correct answer would be -
1- YR, Yr, yR and yr.
2. Yr, yR
3. YR, yr
4. YR, Yr, yR & yr
Explanation:
A mature male or female haploid germ cell that fuses with another gamete of the opposite sex during the process of fertilization to make a zygote in sexual reproduction.
The law of Independent Assortment presented by Mendel says that alleles for different traits are passed and assort independently of one another in the gametes.
1. If Y and R on different chromosomes then they will produce four gametes and assort independently - YR, Yr, yR & yr.
2) If Y and R on the same chromosomes and no crossing over occurs then they will produce only two gametes as Y and R will not come together - Yr & yR.
3). if dominant Y and recessive r are on the same chromosome, no crossing over then only two gametes will form as Y and r will not assort together - YR & yr.
4). if dominant Y and R are on the same chromosome, 50% crossing over produces 4 types of gametes, YR, Yr, yR & yr.