Answer:
He extracted and observed DNA from white blood cells.
Explanation:
Friedrich Miescher, who is a Swedish Botanist, is the scientist who isolated for the first time. In 1869, Miescher isolated a chemical he called NUCLEIN, which is called Nucleic acid now.
He discovered this so called "NUCLEIN" substance from the nuclei of white blood cells. Nucleic acids are the DNA and RNA we know today, hence, Miescher's discovery was significant to the genetic code as he even agitated for the inclusion of his discovery into inheritance.
Answer:
The cell wall is like the integumentary system of the human body because they both protect the interior from the external environment.
Explanation:
Answer:
A huge number of chemical reactions take place continuously in a living cell. The whole of all chemical processes, that is, the total turnover of matter and energy is called metabolism.
Explanation:
All organisms need the energy to grow, reproduce, and respond to their surroundings. All these processes are achieved through metabolism that allows the energy available to them.
If the stimulus frequency is so high that the relaxation phase disappears completely, contractions become continuous in a process called complete tetanus.
What is tetanic contraction?
- When the motor neuron that innervates a skeletal muscle generates action potentials at an extremely rapid rate, a persistent muscular contraction known as a tetanic contraction is induced.
- A motor unit has experienced its motor neuron's maximum stimulation during this state, which lasts for a while. This happens when several impulses with a high enough frequency excite the motor unit of a muscle.
- Every trigger results in a twitch. A slow enough stimulus delivery will cause the muscular tension to release between each succeeding twitch. High frequency stimulation will cause the twitches to overlap, which will cause tetanic contraction.
Learn more about the Nervous system with the help of the following link:
brainly.com/question/3239081
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True, Chordates are animals in Phylum Chordata.Chordates include all of the vertebrates, in which the notochord develops into a backbone, as well as some invertebrates. Invertebrate chordates include tunicates and lancelets.