Flucuated between hot and cold periods
Answer:
Megaspore—2n.
Explanation:
Angiosperms are the fruit bearing plants and reproduce by the process of sexual reproduction. The chromosome number are specific at each stage of the cell cycle of the angiosperms.
Microspores , egg are haploid. Zygote is diploid in nature. Megaspores get germinate into the female gametophytes and these are haploid in nature. Megaspores are also haploid in angiosperms.
Thus, the correct answer is option (b).
Answer:
Chitin, Cellulose and Peptidoglycan (B, C and D)
Explanation:
Both chitin and cellulose are composed mainly of glucides, bound by glycosidic bonds of the Beta 1-4 type. This is largely why they cannot be digested by most non-herbivorous animals.
As for peptidoglycans, it is a net. It is a molecular framework present in bacteria that has β1-4 and α1-4 bonds in different proportions.
Look up a food web in google images, then count the total organisms to 25 and that should give you the answer.
Answer:
The Rhizaria are supergroup species of mostly unicellular eukaryotes and classified as protista. Rhizaria include species like cercozoa, foraminifera and radiolaria.
<u>Some of the attributes of Rhizaria are:</u>
- non-photosynthethic in nature, but some have a symbiotic relationship with unicellular algae.
- express only rDNA sequences so they can vary in different forms.
- do not have clear morphological characters
- they mostly includes amoebas which functions for food engulfing and help to direct movement in rhizarian protista.
<u>Contribution of Rhizaria to the ecosystem:</u>
- There are known as abundant bacterial grazers, and play very important role in microbial food webs.
- They provide a wide diversity of marine organisms.
- important contributors to oceanic carbon pools .
Hence, Rhizaria are important part of ecosystem.
