Answer:
the third one is correct
explanation
because atomic number and proton &electron number is same . neutron number is solved as atomic mass minus atomic number ( N=atomic mass - atomic number)
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.
Producers are where the cellular respiration occur in the biosphere.
Answer: Substances that are protein based cannot cross the lipid cell membrane, but can exert their effect by binding to the proteins based receptors present on the lipid bilayer.
Explanation:
Hormones such as calcitonin , Parathyroid hormone and pituatry horomones are proteins and water soluble.They cannot cross lipid bilayer but can bind to ligand binding protein receptors.
These receptors are protein macromolecules that are specific in nature for specific hormones.
After binding to the receptors, these hormone-recpetor complexes activate second messengers and regulate the downstream effects.
Answer:
Explanation:
The spores of some fungi are dispersed in water or on the surface of water. The chemical composition of the wall of these spores makes them "non-wettable" so they won't sink. The spores are carried along on the surface of the water like little boats. Water in the form of raindrops can disperse spores in a different way. While gravity is not a primary means of spore dispersal, evolutionary adaptations have been required of many fungi to overcome gravitational effects for effective spore dispersal. SPORE DISPERSAL BY WIND Dispersal of fungal spores by wind is by far the most common method for terrestrial fungi.