Answer:
More information required
Explanation:
Is there a picture you forgot to post with the question?
In the problem you mention, which I assume comes from the study of finches in the Galapagos, some birds evolved to have different beaks, depending on the food available. Depending on what kind of seeds there are, different beak sizes were selected for, with those with the right fit eventually winning out over the rest on the individual islands.
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:
Extraction of oil from tar sands is not economically feasible.
Explanation:
Answer:
increasing extension time
Explanation:
The Polymerase Chain Reaction is a technique widely used in molecular biology laboratories to amplify target DNA regions. The standard steps of a PCR are as follow 1-denaturation, 2-annealing and 3-elongation/extension. These steps are repeated 15-40 times in order to exponentially amplify the linear DNA fragment. It is well known that longer extension times can be used as a strategy to increase the yield of longer PCR products. This is because the extension time depends on the synthesis rate of the DNA polymerase used in PCR technique and the length of the DNA fragment to be amplified.
Answer: C) The subplate neurons attract the appropriate thalamic axons to the different parts.
Explanation:
Subplate neurons are the first developed neurons can be found in the cortex of mammals. These neurons disappear during the process of postnatal development and due to functional maturation.
These neurons are sensitive to the injury, when the humans experience cognitive and motor defects.
These neurons attract the thalamic axons and receive the synaptic inputs through the thalamic axons thus helps in establishing the link between the thalamic axons and the target layer IV. The signals are distributed from the thalamic axons to different parts of the body.