DNA is the correct answer but next time put answer choices so that people can better answer your questions. Thanks!
Answer:
arthropoda : invertebrate
mollusca : invertebrate
chordata : vertebrate
Explanation:
There are 9 in total but those are the main 3
They have a cell membrane, they contain cytoplasm and can replicate themselves through the manner of mitosis.
Recombinant DNA is a type of artificial DNA which have genes that are taken from different organisms. During this process, a gene is take from one organism and putting the gene into another organism. Basically, the technology follows cut and paste scheme to form the new brand of DNA.
So to conclude this the technology cuts part of the DNA out to create a new DNA so you are cutting and pasting new DNA which is incredible.
Hope this helped.
Calcium levels in the body are maintained by hormones. If the blood calcium level rises above a set point, calcitonin is secreted by the thyroid gland and sets into motion responses to lower the blood calcium back to the set point. If the blood calcium level falls below a set point, the parathyroid gland secretes parathyroid hormone that sets into motion responses to raise the blood calcium. These homeostatic responses are examples of:
a. positive feedback
b. effectors
c. sensors
d. negative feedback
Answer:
d. negative feedback
Explanation:
Negative feedback responses are the ones that counteract the change. Any alterations in the internal body conditions such as blood calcium levels are sensed by receptors. The information is sent to the brain which in turn commands the effectors such as endocrine glands to secrete the required hormones to restore the normal conditions. Here, changes in the calcium levels are counteracted by the secretion of calcitonin and parathyroid hormones and the calcium is maintained within a narrow range. This represents negative feedback.
