Answer:
The mass of a star determines its life cycle, that is, more the mass, shorter will be its life cycle. The mass of the star is determined by the concentration of matter, which is found within its nebula. In the nebula, with time, the hydrogen gas comes in close proximity with each other due to gravity and starts to spin.
With the brisk spinning, the gas heats up and turns into a protostar. The temperature now reaches 15,000,000 degrees and within the core of the cloud, the phenomenon of nuclear fusion takes place. The cloud now contracts a little, starts to glow brightly, and turns stable. The cloud now becomes a prime sequence star, and will stay in this phase for millions of years, the Sun of our galaxy is in this stage at the moment.
Answer:
I) Presence of nuclear envelope
II) Presence of membrane-bounded organelles
Explanation:
Unlike prokaryotic cells, eukaryotic cells possesses nuclear membrane and membrane-bound organelles. As a result, they undergo mitosis and meiosis.
Examples of organisms with Prokaryotic cell are bacteria, cyanobacteria
Examples of organisms with eukaryotic cells are green plants, fruitfly etc
Answer:
(a) can be used to bend epithelial sheets into tubes.
Explanation:
The adherens junctions are cell-cell adhesions localized in places exposed to abrasion or mechanical stress, close to the apical membrane in epithelial cells is one of these locations. Some of their functions are the initiation and stabilization of cell-cell adhesion, <em>they join the actin cytoskeleton to the plasma membrane to form adhesive contacts between cells that contribute to the folding and bending of epithelial sheets,</em> therefore they can mediate adhesion and signaling.
I hope you find this information useful and interesting! Good luck!
Can you take a closer picture please.
Some plants have a complex life cycle that includes the sporophyte and,gametophyte stages.