Answer:
miRNA ( micro RNA )
Explanation:
The small RNA molecule that interfere with gene expression are miRNA. The miRNA is micro RNA that are non-coding molecules of RNA. These small RNA regulate gene expression after transcription (post transcription).
The miRNA binds to 3' UTR region (untranslated region ) and halt the process of protein production and thereby silencing mRNA.
The right answer is inversion.
Inversion is a genetic mutation characterized by the end-to-end reversal of a portion of chromatid on a chromosome.
In other words, it is a double break then it is replaced after rotation of 180 ° of a chromosome segment (backward insertion).
We distinguish :
Paracentric inversions: The centromere in the chromosome is not included in the inversion.
Pericentric inversions: The centromere is included in the inversion which transforms a metacentric chromosome into an acrocentric chromosome.
Answer:
True
Explanation:
gametes from two plant species can combine and produce a haploid zygote
Answer:
B. puberty because it's still a stage of pre adult hood
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.
