Answer: New research shows that colonies of Escherichia coli can demonstrate a form of learning.
Explanation: Bacterial colonies can evolve the ability to anticipate changes in their immediate environment, say researchers led by Saeed Tavazoie at Princeton University in New Jersey. Other types of bacteria could too. This skill could give them the edge over other bacteria that merely adapt themselves to current conditions.
Answer:
B) You measure the quantity of the appropriate pre-mRNA in various cell types and find they are all the same.
Explanation:
In the above scenario, we are using the control gene and we should know about the control gene is that its expression is either at transcription level or at translation level. For this situation we should examine the pre-mRNA stage of control gene in various cells because it is control gene so it should be present in various cells.
So, the best practice is to quantify the pre-mRNA level of gene then we can effectively solve the experimental problem and find the gene expression either it is at transcription or translation level.
Answer: B. secrete enzymes that kill bacteria
Explanation:
Paneth cells, so-called because they were first described by Dr. Josef Paneth in 1888, are pyramidal cells, with the nucleus in the basal position, and with large granules in the apical position. Its first isolated specific product was the lysozyme, a bactericidal substance, by Alexander Flemming. These cells play an important role in innate immunity in the small intestine, producing a wide diversity of antimicrobial peptides and enzymes such as lysozyme itself, cryptidines, defensins and a lectin with bactericidal properties.
Answer:
C) They are compressed during inhalation.
Explanation:
Birds breathe through rigid lungs that are located in the animal's thoracic region. The trachea of birds divides into bronchi that branch inside the lungs into very thin tubes called parabronchials or parabroncholes, which are irrigated by blood capillaries that allow gas exchange.
In birds there are no pulmonary alveoli (as in mammals), but air capillaries that depart from the parabroncholes. Oxygen gas passes from these capillaries to the blood capillaries, thus causing gas exchange.
In the lower portion of the bird's trachea, before branching the bronchi, we can find the syringe, a bag-like structure that has vocal cords responsible for the birds' scream and song. Most of the time, the sound emitted by birds serves to attract the mate, mark territory and prevent birds of the same species against some predator or other danger.
Genes and the environment
