Answer:
<u>Antigenic drift</u> refers to the slow accumulation of genetic changes to an influenza virus over time.
Explanation:
Antigenic drift is defined as the mechanism by which viruses undergo variation. This mechanism involves the slow accumulation of mutations in the viral genes, that are responsible for coding the antibody binding sites. This leads to the formation of a new strain of virus, which can't be inhibited by the old antibodies. Due to this, the virus can easily spread the disease.
The antigenic drift occurs in the influenza A virus and also the influenza B viruses.
Therefore, <u>Antigenic drift refers to the slow accumulation of genetic changes to an influenza virus over time.</u>
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.
If this division is based on tissue formation then it is correct because there are 8 types of cells. If it's based on the function then it's incorrect because there are more than 10.
The sewing needle should float in the water if placed on a horizontal angle if I remember properly.
I hope this helps in some way.
Answer:
B- fold incorrectly
Explanation:
Prions are misfolded proteins with the ability to transmit their misfolded shape onto normal variants of the same protein. They characterize several fatal and transmissible neurodegenerative diseases in humans and many other animals.