Question

In Melandrium, sex determination is of _____type.
(A) XX - XO
(B) ZZ-ZW
(С) XX-XY
(D) XY – XO

Answer 1

Hint: The sex determination during a plant is most almost like the sex determination plants. The sex chromosomes which are present within the plants will determine the sex of the parts of the plants alike to the plants. we will say that males are XY and XX are female. The dioecious prototypical plant white campion. (a) Female and (b) male flowers, that's one among both the calyx and corolla will get detached to point out pistils and stamens, correspondingly.

Complete Answer:
The chromosome which was almost like both males and females was identified as X and therefore the one in male was identified as Y.
- This was proposed by H.E. Warmke. He said and observed that AAXX are going to be the chromosomal constitution of females and AAXY for the males regardless of the ploidy of the chromosomes i.e, the plants are often diploids, triploids or tetraploids.
- Thus the chromosome composition in males are often XY, XXY, XXXY, XXXXY. The males with XXXXY chromosomes are hermaphrodites which suggests one Y is capable of 4X.

Now allow us to collect information about given options :
(A) XX – XO: It's observed in a sizable amount of insects e.g., Grasshopper. Number of chromosomes are different in male and female individuals.
(B) ZZ-ZW: In birds, both the sexes possess two sex chromosomes. Unlike citizenry, the females contain heteromorphic sex chromosomes while the males have homomorphic sex chromosomes. due to having heteromorphic sex chromosomes, the females are heterogametic.
(С) XX-XY: Melandrium album (2n=24) could also be a dioecious species with heteromorphic sex chromosomes represented as (XY in males and XX in females). Through the microscopic study was seen that the chromosomes in males differed in appearance thereto of females.
(D) XY – XO: during this type male individual produces two differing types of gametes. Thus, the sperm determines the sex of the offspring. It involves two kinds of sex determining mechanisms; XO type and XY type.

Hence the correct answer is option C that's XX – XY.

Note: Establishment of sex through differential development during a private at an early stage of life is known as sex determination. Different species use very different strategies for this purpose. Some organisms like turtles rely entirely on environmental factors like temperature for sex determination. Sex of citizenry and insects like grasshopper, firefly, Drosophila etc. is decided genetically. The initial clue about the genetic or chromosomal mechanism of sex determination are often traced back to a number of the experiments administered in insects.