Answer:D
Explanation: The pulmonary air sacs of birds only permit a unidirectional flow of air through the lungs. Unidirectional flow means that air is inhale and exhale through one trachea alternatively. This means the bird lungs only receive largely fresh air which has a high oxygen content during inhalation and do not receive fresh during exhalation. While air flow bidirectional in mammals.
Freshwater does not contain any salt, salt water does however contain salt.
Answer:
The way they classify this practice is known as "Matrilineal"
Explanation:
Matrilineal tells us about the mother's line, this is basically done to restore the traits that are present in mother side. It is an important part of the anthropology. This phenomenon determines the heir of the property after the death of the property owner. In general terms it is the relative, behavior or other traits that has been traced through the mother lineage. They have the exogamic blood kin which is being related to mother line. Also referred as "Those from one womb or one bone".
Answer:
A.Dissolving salt in water
Explanation:
Hope it helps
Explanation:

Seed formation without fertilization in flowering plants involves the process of ---
A) APOMIXIS