C. <span>eukaryotic cells contain organelles that are enclosed in membranes.</span>
Plants living in dry areas face conflict.
EXPLANATION:
- Since they live in dry areas they will undergo more transpiration.
- If they open stomata during the day there will be excessive loss of water vapor that will result in their death.
- Therefore plants living in this area open the stomata during the night to obtain Carbon dioxide.
- This checks the loss of water through transpiration and provides the carbon dioxide for photosynthesis.
Answer:
a) False.
b) True.
c) False.
d) True.
e) False.
f) True
g) True.
Explanation:
a) The main characteristic of homologous chromosomes is that they have an equal size. There is a difference in size on both chromosomes.
b) In number one, two chromosomes are homologous. In number two also two chromosomes are homologous. On the other hand, the chromosomes at number one and two are different. Each chromosome has two sister chromatids.
c) A DNA molecule has a double helix, that is, two chains. When a DNA chain is broken and a chromatide has a DNA chain, then two chromatids make up a chromosome and a DNA chain, in this way there are eight dsDNA molecules
d) If each chromosome contains a centromere, therefore, there are four centromeres on all four chromosomes.
e) If a chromosome contains four telomeres, therefore there will be sixteen telomeres.
f) The function of cohesin is to regulate the separation of chromatids in the cell division process. When DNA replication is complete, the DNA compacts and condenses to form mitotic chromosomes.
g) The CENPA protein is encoded by the CENPA gene.
The KT boundary marks a mass extinction event. the KT boundary is the time between the Cretaceous and Tertiary periods. An asteroid hit the earth at the end of the Cretaceous and that caused the end of the Cretaceous period. Before the KT boundary, pollen from angiosperms and gymnosperms is high. After the meteor hits the earth, a mass extinction occurs and the amount of pollen from gymnosperms and angiosperms decreases dramatically, while the amount of spores from ferns increases. During the Cretaceous period there were many species of gymnosperms and angiosperms but they disappeared at the KT boundary, when the asteroid hit the earth.
So you know what is what and where it goes
