Answer:
D. the 23rd pair of chromosomes
Explanation:
Humans have a total of 23 pairs of chromosomes. Out of a total of 23 pairs, 22 pairs are autosomes. Autosomes are the chromosomes that carry the genes for all the genetic traits but are not involved in the sex determination of the individuals.
The 23rd pair of chromosomes in humans is of sex chromosomes as these chromosomes carry the genes to regulate the gender of the individuals. A human female has two copies of the X chromosome as sex chromosomes while human males have one X and one Y chromosome as their sex chromosomes. The Y chromosome carries "SRY" gene that codes for testes determining factor and regulates the development of testes in the embryo.
Answer:
Commensalism only occur among biotic factors
Explanation:
Abiotic factors are non-living factors that interacts with the biotic factor within an ecosystem. Commensalism is an association between two organisms in which one benefits and the other derives neither benefit nor harm.
From the above definition of commensalism, it is clear to note that it only involves two organisms rather than non-living organisms, hence; commensalism involves only biotic factors
Answer:
After you swallow, peristalsis pushes the food down your esophagus into your stomach. Stomach. Glands in your stomach lining make stomach acid and enzymes that break down food. Muscles of your stomach mix the food with these digestive juices.
Explanation:
B cause they all blend in with snow so they can survive
The lac operon contains an operator, promoter, and structural genes that are transcribed together and are under the control of the catabolite activator protein (CAP) or repressor.The lac operon encodes for the genes needed to utilize lactose as an energy source. Answer is C