-Surface area to volume ratio. (surface area / volume)
-Nucleo-cytoplasmic ratio.
-Fragility of cell membrane.
-Mechanical structures necessary to hold the cell together (and the contents of the cell in place)
A phylogenetic tree<span> or evolutionary </span>tree<span> is a branching diagram or "</span>tree<span>" showing the inferred evolutionary relationships among various biological species or other entities—their </span>phylogeny<span>—based upon similarities and differences in their physical or genetic characteristics.</span>
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.
Answer:
The second statement is correct: "The "host range" for a virus is determined by the presence or absence of particular components on the surface of a host cell that are required for the virus to attach."
Explanation:
The virus attaching itself to the host cell is the first step for it to successfully infect the host. Viruses are smaller in size than bacteria, so the first statement is incorrect. The third statement is incorrect because viruses do not have the necessary machinery to carry out protein synthesis or to generate ATP, this precisely why they seek out a host to begin with. The fourth statement is false because the virus will either have DNA or RNA, but both at the same time.
Hope that answers the question, have a great day!
