Answer:
Convergent Evolution
Explanation:
Convergent evolution occurs when two unrelated species that have no common ancestor evolve independently in order to adapt to a similar environmental constraints to ensure survival.
An example of convergent evolution can be seen in birds, bats, flight/wing insects. They all do not share a common ancestor, but have evolved, separately, a similar structure for flight.
Another example can be seen in dolphins and sharks. These two different species share similar physical characteristics that make them adapt well in marine habitat that helps them to predate
.
The answers are:
A. DNA replication in the nucleus of a cell
B. From one helix of DNA in a replication process, we get two: The DNA is a double helix and it consists of two strands of specifically connected amino-acids. When the time for replication comes, a set of enzymes unwind the two strands and leave them as a base for additional two strands attaching to them - the green line is an example of that. The free nucleotides - adenine, guanine, thymine and cytosine are left open and the enzyme called DNA-polymerase helps to produce a new strand on the template of the old parental one (one of the blue ones in the picture)
C. By the location on the smaller picture - replication takes place in the nucleus. And the most important hint are the letters A - adenine, G - guanine, T- thymine, and C-cytosine. A connects with T, and G connects with C.
Answer:
d. The normal pH of human blood is already in the alkaline range.
Explanation:
The blood has an average pH between 7.35 and 7.45. Also, in blood there are some natural buffers that allows to maintain this pH does not matter the kind of food or substances that enter to our body.
If for any process the pH decreases a little bit, the body starts a process to recover the natural pH of the blood.
Provided that there's no diagram, most molecules have particular areas on the molecules, called the "active area" that act as a lock to a particular substrate's molecular structure, providing the key.
An enzyme's active area is only able to be "unlocked" by a certain substrate's "key".
The plant cell is the smallest living structure and constituent unit of all plants. Its size and shape vary by function. It is composed of several organelles, all useful to its activity.
The right answers are: (the numbers are in the picture).
1 refer to a vacuole.
2 refer to a cell wall (if you see closer, the arrow is aiming the green layer, the yellow one is the cell membrane).
3. refer to a chloroplast.
4. refer to mitochondria.