The mass number is the sum of the number of protons and number of neutrons the atom has.
So, we can write the equation as:
x + 20 = 40
x = 20 neutrons.
Answer: Change between generations
Explanation:
Heredity involves the passing of characteristics or traits from one generation to the next. It accounts for the reason as to why offspring look like their parents.
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.
