Answer: C
Explanation: In anaphase 1 in meiosis, homologous pairs are separated but sister chromatids stay joined together. In anaphase 1 of mitosis the sister chromatids do separate.
Answer:
The flower colour ratio obtained is: Blue : Purple = 3 : 1.
Explanation:
- According to the question,
- the genotype, AABB or AaBb or AABb or AaBB gives blue phenotype.
- the genotype, AAbb or aaBB or Aabb or aaBb gives purple phenotype.
- Red phenotype is for the aabb genotype.
- As only the presence of dominant allele is mentioned but whether it is homozygous or heterozygous is not mentioned, in 1. we consider that presence of a single dominant allele A or B in either locus is capable of showing a blue phenotype, irrespective of the nature of the other allele.
- In 2. we consider that the presence of a single dominant allele, A or B in one locus with recessive pairs of alleles in the other locus is sufficient to develop the purple phenotype.
- The aaBb individual will produce the gametes: aB, ab.
- The AABb individual will produce the gametes: AB, Ab.
- Crossing them,
aB ab
AB AaBB AaBb
(Blue) (Blue)
Ab AaBb Aabb
(Blue) (Purple)
- Of the offspring obtained, 3 have blue phenotype and 1 has purple phenotype.
- Hence, they have the following phenotypic ratio:
Blue : Purple = 3 : 1.
Answer:
The organisms reproduce in two ways:
Asexual Reproduction– In this process, only a single parent is involved and no gamete formation takes place.
Sexual Reproduction– In this process, two parents are involved and gamete formation takes place. Meiosis is an important step in sexual reproduction.
Key Points on How do organisms reproduce
- Reproduction is the process of producing new individuals of the same kind.
- Organisms reproduce in two ways- asexually and sexually.
- Asexual reproduction does not involve the fusion of male and female gametes. This takes place in bacteria, amoeba, hydra, etc.
- Sexual reproduction involves the fusion of male and female gametes and can be seen in humans and many animals.
- Fission, budding, vegetative propagation, fragmentation are some different types of asexual reproduction. It does not require any reproductive organs.
- Sexual reproduction involves the reproductive organs of male and female.
Answer:
Groundwater moves very slowly through the aquifers at a rate of only inches per day. Some contaminants that reach the groundwater break down slowly or not at all, and move slowly with the water. Therefore, groundwater may contain these contaminants for many years.
Explanation:
