The correct answer of the given question above would be option D. The option that did not occur during the Cenozoic era is the formation of the ozone layer. The ozone layer has long been there before any era since it is part of the earth's atmosphere. Hope this answer helps.
It adds bases in only one direction.
Answer:
The correct answers are:
1. closing
2. the ventricles and arteries,
3. a constricted trachea
Lub is the first sound of a heartbeat and is mentioned as S1. It is usually produced due to the closing of tricuspid and and mitral or bicuspid valves present between atria and ventricles.
Tricupsid is located between atrium and ventricle of the right hand side and mitral valve is located between atrium and ventricle of the left hand side. They prevent the back flow of blood from ventricles to their respective atria.
Dub, being the second sound is written as S2. It is produced due to the closing of pulmonary (located between right ventricle and pulmonary artery) and aortic valves (located between left artery and aorta).
These valves prevent the back flow of blood from arteries into the ventricles.
The time between the two sounds is often taken as the measure of the diastole i.e. ventricular filling.
Wheezing refers to a high-pitched sound produced when a person breathes, especially during exhale. It is caused by constriction of the airways or inflammation. It is considered as a symptom of various diseases such as asthma, COPD, allergies, bronchitis etc.
Abiotic factors are factors that include non-living parts of the environment which could be significant or essential to living organisms. Water is a non-living environment and it helps in giving life to plants and other organisms. Thus deemed abiotic.
Answer:
This question lacks options, however, primary succession will be explained for detailed comprehension.
Explanation:
Ecological succession is the gradual series of changes that occurs in an ecosystem, charging it's structure and composition over time. It is of two types namely; primary and secondary successions.
Primary succession is characterized by the "LACK OF NO SOIL". It begins on a barren piece of land e.g rocks, with no form of life previously known to colonize the area. In primary succession, the barren land is first colonized by organisms such as lichens etc., which are collectively regarded to as PIONEER SPECIES.
