Answer:
10 chromosomes/sister chromatids
Explanation:
Prophase is the first stage of cell division (mitosis). Prior to the cell entering the actual division stage, it undergoes a phase where it prepares its content and most importantly undergo the duplication of its genetic material (DNA). This DNA are found as chromosomes. It undergoes replication of its DNA in the S-phase of interphase stage.
Since Arabidopsis thaliana has 10 chromosomes, and each chromosome holds one DNA molecule, 10 molecules of DNA will be present in the mustard plant's genome. These 10 molecules of DNA will be replicated on another copy of chromosome which is identical to the template. This chromosomes are called SISTER chromatids i.e. replicated chromosome. Each sister chromatids are held together at the centromere and are considered one individual chromosome until they separate during anaphase stage.
Hence, at the Prophase stage, before separation, each sister chromatid (replicated chromosome) is considered as one chromosome. Thus, in the mustard plant with 10 chromosomes, it will possess 10 sister chromatids or chromosomes at the Prophase stage.
N.B: When sister chromatids separate during anaphase stage, they will be regarded as individual chromosomes.
Answer:
We learned in biology class that every cell in the body has the same DNA. Whether a heart cell, skin cell or muscle cell—they all read from the same genetic blueprint. Now, scientists are learning there is more to the story.
Explained in greater detail, each gene resides at a specific locus (location on a chromosome) in two copies, one copy of the gene inherited from each parent. The copies, however, are not necessarily the same. When the copies of a gene differ from each other, they are known as alleles.
