Answer:
By action potential nerve contract the muscle
Explanation:
The muscle contract when the nervous system sends action potential to the muscle. So the nervous system delivers signal to muscle, the first signal reaches the neuromuscular junction. The signals are passed by a chemical messenger called neurotransmitter release by motor neurons, the chemicals bring reaction and shorten the muscle fibre. When neurotransmitter are absent or reduce in concentration the process reverse and muscle relax again.
 
        
             
        
        
        
When two paired chromosomes harbor the same or identical alleles for a given characteristic at nearby loci, this condition is referred to as homologous (i.e. homologous chromosomes)a diploid organism or cell that has the same allele for both a maternal and paternal gene.
The term "homozygous" refers to the presence of the same or identical alleles for a given trait at related loci on paired chromosomes (i.e. homologous chromosomes). An entity with two sets of chromosomes is said to be diploid. Both sets are inherited; one set is from the mother and the other from the father. Based on their locations, each maternal chromosome can be matched with a corresponding paternal chromosome. Homozygous occurs when the same alleles are present at the loci in the corresponding chromosomes. It indicates that the same trait is coded for by both alleles.
A "homozygous" organism is one that carries two copies of either a pair of dominant alleles (such as AA) or a pair of recessive alleles for a given trait. genuinely reproducing organisms
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Answer:
1. Buccal cavity (oral cavity) and the nasal passage opens into Pharynx. Pharynx opens into esophagus of the digestive system and opens into larynx of the respiratory system.
2. It is an organ which is found in both vertebrates and non-vertebrates. However, the structure may vary from species to species.
3. The word “Pharynx” is derived from the Greek words “Pharunx” or “Pharung”. Its plural form is pharynges.
Explanation:
 
        
                    
             
        
        
        
<span>each set of three nitrogen bases representing an amino acid is referred to as a condon.</span>
        
             
        
        
        
There are two types of cell division: mitosis and meiosis. Most of the time when people refer to “cell division,” they mean mitosis, the process of making new body cells. Meiosis is the type of cell division that creates egg and sperm cells.
Mitosis is a fundamental process for life. During mitosis, a cell duplicates all of its contents, including its chromosomes, and splits to form two identical daughter cells. Because this process is so critical, the steps of mitosis are carefully controlled by a number of genes. When mitosis is not regulated correctly, health problems such as cancer can result.
The other type of cell division, meiosis, ensures that humans have the same number of chromosomes in each generation. It is a two-step process that reduces the chromosome number by half—from 46 to 23—to form sperm and egg cells. When the sperm and egg cells unite at conception, each contributes 23 chromosomes so the resulting embryo will have the usual 46. Meiosis also allows genetic variation through a process of DNA shuffling while the cells are dividing.