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.
1.each of several hierarchical levels in an ecosystem, comprising organisms that share the same function in the food chain and the same nutritional relationship to the primary sources of energy.
A scavenger is an organism that mostly consumes decaying biomass, such as meat or rotting plant material. Many scavengers are a type of carnivore, which is an organism that eats meat. While most carnivores hunt and kill their prey, scavengers usually consume animals that have either died of natural causes or been killed by another carnivore.
Scavengers are a part of the food web, a description of which organisms eat which other organisms in the wild. Organisms in the food web are grouped into trophic, or nutritional, levels. There are three trophic levels. Autotrophs, organisms that produce their own food, are the first trophic level. These include plants and algae. Herbivores, or organisms that consume plants and other autotrophs, are the second trophic level. Scavengers, other carnivores, and omnivores, organisms that consume both plants and animals, are the third trophic level.
Nitrogen is converted from atmospheric nitrogen (N2) into usable forms, such as NO2-, in a process known as fixation. The majority of nitrogen is fixed by bacteria, most of which are symbiotic with plants. Recently fixed ammonia is then converted to biologically useful forms by specialized bacteria.
Answer:
C. levels of specific hormones
Answer: D. Galaxies show a red shift, indicating they are moving away from each other.
Explanation:
Galaxies seem to show a red shift which indicates that the galaxies are moving away from each other. This provides evidence for the Big Bang theory because the theory posits galaxies will keep moving away from each other.
This is because when an explosion happens, matter moves away from the point where the explosion happened. If the Big Bang happened therefore, galaxies will move away from the source which is why galaxies are moving away from each other.
The answer is Triton.Triton <span>is the largest of Neptune's </span>satellites. Triton is unique as it is the only large moon in the Solar System with a rotation opposite that of its planet. The surface of Triton is mostly frozen nitrogen, with a water-ice crust and a rock and metal core.
