1. Answer: A
Explanation: For a cell to form proteins, the specific types of proteins are coded for by the genes in DNA (found in the chromosomes of the nucleus). To produce proteins, the genes are first transcribed by RNA polymerase to form messenger-RNA. The mRNA is then translated into proteins by ribosomes in the cytoplasm of the cell.
2. Answer: B
Explanation: Translation of genes into proteins is dependent on the sequence of nucleotides. They are translated in sequences of 3 nucleotides known as codons. Therefore adding a nucleotide on a piece of DNA causes what is referred to as a frame-shift mutation. The 3 sequences (of codons) is interrupted and shifted by one nucleotide. Therefore, the codons change and the amino acids translated will also change.
3. Answer: A
Expanation: Producers are significant in a food chain because they incorporate the energy of the sun into the food chain. This is why they are at the base of the food chain and have the largest biomass. They are consumed by primary consumers which are consumed by secondary consumers which are consumed by tertiary consumers and so on.
4. Answer: D
Explanation: Plants are consumed by herbivores. Therefore, a decrease in plant population due to drought was resulted to decrease in herbivore population. This is due to stiff competition by the herbivores for the scarce plant population. Carnivores consume herbivores. Due to a decrease in the herbivore population, then the carnivore population would also decrease.
5. Answer: A
Explanation: Burning of fossil fuels emits carbon dioxide gas which is a greenhouse gas. Greenhouse gas traps infrared wavelength of lights hence warming up the atmosphere, causing global warming. Reduction in use of fossil fuels will hence alleviate an increase in global temperature hence protect coral in the oceans from bleaching.
<h3><u>Answer;</u></h3>
Rock
<h3><u>Explanation</u>;</h3>
- Rock is a naturally occurring solid mixture of one or more minerals or organic matter.
- <em><u>Rock is a solid mixture of crystals of one or more minerals, or organic matter.
</u></em>
- <em><u>Rocks are classified by how they are formed, their composition, and texture. </u></em>Rock has been an important natural resource as long as humans have existed.
- The rock cycle is the series of processes in which a rock type changes from one type to another.
Answer: Natural selection is one of the forces of evolution and the enviroment where the species lives is the selection agent. For example, suppose a mosquitoes population in a environment free from insecticides, in this environment there's a high frequency of non-resistant mosquitoes because the environment is not exerting any pressure on the resistence trait. But when the environment changes and we use a insecticide upon the mosquitoes population, the populations changes because the non-resistant ones die but those resistant survive and beggin to reproduce more effectively. That's natural selection, differences in survival and reproduction between individuals with different phenotypes (traits) and this differences depend of environmental changes.
Answer:
The last one: dinosaur footprints preserved in mud turned to rock
Fossils have to be physical remains of an animal.
Hope this helps!
Answer:
Brain cells are very sensitive to a lack of oxygen. Some brain cells start dying less than 5 minutes after their oxygen supply disappears. As a result, brain hypoxia can rapidly cause severe brain damage or death.
Explanation:
Other symptoms can include: hallucinations and delusions; increased agitation and confusion; depression and other mood disorders; personality changes, such as irritability and a reduced threshold for frustration; and an inability to focus or concentrate.