The falling progesterone in the secretory endometrium results in the decidua locally producing prostaglandin. Prostaglandin causes vasospasm of... View Article
Once ovulation occurs, the corpus luteum secretes progesterone yielding serum concentrations of the hormone. This rate of steroid production by... View Article
Lignified secondary cell walls typically are impermeable to water. Hence, the only way that water is exchanged between the cells is through the... View Article
Transfer cells are altered parenchyma cells that comprise several cell wall ingrowths. This feature in them enables cells to improve the... View Article
Basis the nature of fossilization, fossils are grouped into several types. Coal balls are one of the types. Coal balls are petrified plant organs... View Article
On the basis of the nature of fossilization, fossils are grouped into many types. Compression fossils are a type of fossil. They are formed due... View Article
Based on the nature of fossilization, fossils are grouped into many types. It is a type of fossil. Rocks sometimes take the form of a few plant... View Article
Copal belongs to the group of hard resins comprising a little essential oil only. They find applications in the varnish industry as a result of... View Article
Significance of heterospory - Gametophyte development in heterosporous forms is endosporic wherein sporophyte supplies the nutrition for... View Article
In some pteridophytes, the stelar structure is more complex. It comprises two or more concentric rings or vascular tissues and is known as... View Article
Protostele is a non-medullated stele comprising a central core of xylem engirdled by a cluster of phloem. There is a multiple of a single layer... View Article
Large sporangium was seen in primitive fossils pteridophytes. Even in primitive ferns, sporangia are large. However, in advanced forms, reduced... View Article
Sorus is a group of sporangia produced on the adaxial/abaxial surface of the sporophylls in ferns. Based on the pattern of maturation of... View Article
Sorus is a group of sporangia produced on the adaxial/abaxial surface of the sporophylls in ferns. Sporangia sometimes can be either scattered... View Article
It is an abnormality seen in the life cycle of pteridophytes. On several occasions, it is seen that chromosome number is impaired in ferns by the... View Article
It is an abnormality seen in the life cycle of pteridophytes. Sometimes, the regular alternation of chromosome numbers is impaired by the... View Article
Yes, alternation of generation is a survival strategy wherein the plant alternates between different reproductive techniques. Through meiosis,... View Article
Fertilization occurs with the help of water. Cap cells of antheridia are pushed down releasing antherozoids when a film of water flows between... View Article
The zygote develops into an embryo soon after fertilization which differentiates into the seta, foot and sporangium. The foot seeps through the... View Article
