Answer:
In our respiratory system, there is a pair of external nostril situated above the upper lip that receives atmospheric air and passed to the pharynx (a common passage for air and food). The pharynx passed this air to the trachea via larynx (known as the soundbox). The trachea is an extended part which is divided into left and right primary bronchi. Bronchi divide into secondary bronchi, tertiary bronchi, and bronchioles that ending up in thin terminal bronchioles. Each terminal bronchiole constitutes a number of irregular-walled, thin and vascularised bag-like structures called alveoli which are the primary sites of gases exchange.
I found the exercise on the internet and bellow are the options:
"A. Seed cones contain ovules.
B. Germinated seeds are haploid.
C. A pollen tube is used to prevent the fertilization process.
<span>D. Pollen grains undergo meiosis to form egg cells."
The correct answer is D.
There are no seed cones, but pollen cones, where the ovules can be found. Germinated seeds are diploid, not haploid. The pollen tube role is to promote the fertilization process by leading the sperm to the egg, once the sperm in this type of plants do not have flagella and therefore no movement.
The correct answer is D because pollen grains are really the diploid germinative cells that </span><span>produce sperm cells.</span>
The saturation of hemoglobin is <u>100% </u>at the arterial PO₂ of 95 mmg and is <u>75% </u>at the venous PO₂ of 40 mmHg
<h3>Saturation of Hemoglobin</h3>
The saturation of hemoglobin at the arterial PO₂ is 100 percent due to the constant supply of oxygen taken in from the environment. while at the venous PO₂ the hemoglobin is 75% due to the limited supply of oxygen.
Hence we can conclude that The saturation of hemoglobin is <u>100% </u>at the arterial PO₂ of 95 mmg and is <u>75% </u>at the venous PO₂ of 40 mmHg.
Learn more about Hemoglobin : brainly.com/question/10122738
An ecosystem is like a machine that cycles matter by using: captured energy.
Hope this helps (:
