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:
c
Explanation:
because the solid ice will sublime into gas
The medulla, pons, and the cerebellum are three main parts of the hindbrain.
Brain is the centre of the nervous system. It is enclosed in the skull cranium. The primary regions of the brain are the forebrain, midbrain and the hindbrain. The forebrain consists of the cerebrum and diencephalon. The midbrain is a small tubular region between the forebrain and the hindbrain. The hindbrain is made up of the medulla oblongata, pons and cerebellum.
Cerebellum is the second largest portion of the brain which helps in maintaining the body's equillibrium, coordinates muscular movements and body posture. Pons is the structure located in the brain stem which relays impulses from medulla to cerebellum and vice versa. Medulla oblongata is the lowest part of the brain stem controlling involuntary reflexes and has the respiratory and cardiac centres in it controlling respiration and heart beats respectively.
Answer:
A particular population limiting factor or factors must have been removed
Explanation:
The population of the birds must have been kept between 30 and 50 individuals by population limiting factors such as the presence of predators within the community or competition for resources such as food or spaces.
For the population to shoot up to 90 all of a sudden, it may be that one or more of the population limiting factors has been removed from the population. <u>It could be that a major predator has been removed from the community or the competition for food/space is now significantly reduced due to more food/space in the community. </u>