Switch A and D, but other than that your answers are correct.
An astronomical body is an object in space.
A comet is a celestial object consisting of a nucleus of ice and a stream of gas and dust.
A moon is an astronomical body that orbits around a planet.
A galaxy is a system of start held by gravitational attraction.
Answer:
Nitrogen thet cannot be used by organisms. C.
Explanation:
Free nitrogen is simply molecular nitrogen (N2). Nitrogen, in its molecular form, consists of two nitrogen atoms bound together with a tripple bond. Because it is very stable, N2 is typically nonreactive, and takes a lot of energy to break them apart. Among these are the amino acids necessary for life to begin and which are the building blocks DNA is made from. Basically, any nitrogen that is in an organic compound is considered “fixed” nitrogen and N2 is considered to be “free” nitrogen
Organism are referred to as Pluripotent cells
Well you see each of the seeds have developed a special technique that allows their individual seeds to travel further and lower the probability of landing close to the tree and not getting the sunlight it needs
For the berries birds and various animals eat them carrying them away so hopefully they can get more sunlight
Helicopter seeds do the same thing except the sides themselves float away from the tree to get a further distance.
Finally the acorn seeds of the oak tree use the same concept of the berries. Various squirrels do eat these kinds of nuts and bury them in the ground in hopes of finding them later. But due to squirrels not remembering where they buried their acorn seeds the acorns are well away from the tree and start growing.
So you see all of these tree seeds are specially developed to help it get away from the trees. Especially so that they can grow in a much better environment than the one provided to them initially.
Answer:
A protein molecule present in the RBCs, which helps in the transportation of oxygen from the lungs to the different parts of the body and brings back carbon dioxide, that is, collected from different parts of the body back to the lungs is known as hemoglobin.
The general features of hemoglobin are that it comprises four molecules of protein in the form of globulin chains. In adults, the molecules of hemoglobin comprise two beta-globulin chains and two alpha globulin chains, while in infants and fetuses, the beta chains are least found, and is substituted by two gamma chains.
Each globulin chain comprises an essential iron-containing compound porphyrin, which is termed as heme. Together both iron and heme play an essential role in circulating oxygen and carbon dioxide in the blood. This iron gives the red appearance to the blood.