#Question id: 745
#SCPH01 Biochemistry
The structure of RNA differs from that of DNA, as RNA contains:
#Question id: 4955
#SCPH06 I Botany
If relatively small carbonaceous chondrites from space were a significant source of Earthʹs original amino acids, then which two of these would have been most important in permitting their organic materials to survive impact with Earth?
I. Carbonaceous chondrites must contain no D-amino acids.
II. Earthʹs early atmosphere must have had little free oxygen.
III. The chondrites must have arrived on Earth before 4.2 billion years ago.
IV. Earthʹs early atmosphere must have been dense enough to dramatically slow the chondrites before they impacted.
V. The chondrites must have impacted land, rather than a large body of water.
#Question id: 10899
#SCPH05 I Biotechnology
Companion cells transport of photosynthetic products from producing cells in mature leaves to the sieve elements in the minor veins of the leaf. There are at least three different types of companion cells in the minor veins of mature, exporting leaves, All three cell types have dense cytoplasm and abundant mitochondria;
#Question id: 19210
#SCPH06 I Botany
#Question id: 344
#SCPH28 | Zoology
The partial negative charge at one end of a water molecule is attracted to the partial positive charge of another water molecule. What is this attraction called?