Group 15 is called the nitrogen group. The first two elements in this group are nonmetals. These are followed by two metalloids and one metal. All the elements in the nitrogen group have five valence electrons, but they vary in their reactivity.
Answer:
A sporophyte (/spɔːroʊˌfaɪt/) is the diploid multicellular stage in the life cycle of a plant or alga. It develops from the zygote produced when a haploid egg cell is fertilized by a haploid sperm and each sporophyte cell therefore has a double set of chromosomes, one set from each parent.
Explanation:
Answer:
The <u><em>pharynx</em></u> starts an involuntary swallowing action when senses food.The <u><em>esophagus</em></u> squeezes food down the digestive tract by an involuntary synchronized muscle movement called the <u><em>peristalsis</em></u>. Food that has been digested in the <u><em>stomach</em></u> is processed into a thick liquid called <u><em>chyme</em></u>.
Explanation:
Digestion can be described as a process in which food is broken down so that an organism can use the energy in the food. The process of digestion is voluntary in the start as we take in food. But after this, the process of digestion becomes involuntary from the pharynx. The esophagus is the large tract through which food is squeezed into the stomach from the mouth. The squeezing is done by the force generated by muscle movements which is termed as peristalsis.
The main type of evidence the scientists used is fossils.
Palaeontologists study plants and animals that existed in the geologic past. To do so, they use fossils and try to determine an organism's evolution and relationship with the environment and other organisms. In this example, palaeontologists used fossils from ancient horses that have gone extinct and try to decipher their evolutionary path. Recognising the evolutionary steps of the ancient horses will make it possible to compare them to the modern horses.