The smaller breeds of dogs tend to have their first estrus cycle at an earlier age, while the large and giant breeds of dogs may not come into heat for the first time until they reach eighteen months to two years of age.strus is the stage of the reproductive cycle in which the dog can become pregnant; sometimes a dog that is in estrus is said to be in heat or in season. On average, puberty or sexual maturity is reached at about 6 months of age, but this can vary by breed.
What is the function of the respiratory mucosa? As with all mucus in the body, its a lubricant to keep the lungs moist, prevents the lung lining from sticking to itself and prevents foreign body's like bacterium and dust fr â¦ om in bedding into the lungs causing infection.pecialized membrane that lines the air distrubution tubes in the respiratory tree. Over 125ml of mucus produced each day forms a mucous blanket over much of the respiratory â¦ mucosa. Mucus serves as an air purification mechanism by trapping inspired irritants such as dust and pollen etc.
The rest of the cavity is the respiratory portion. The respiratory area is lined with a moist mucous membrane with fine hairlike projections known as cilia, which serve to collect debris. Mucus from cells in the membrane wall also helps to trap particles of dust, carbon, soot, and bacteria. Sinus cavities are located in the bony skull on both sides of the nose. In the olfactory (smelling) portion of the nose, most of the lining is mucous membrane. A small segment of the lining contains the nerve cells that are the actual sensory organs. Fibres, called dendrites, which project from the nerve cells into the nasal cavity, are covered only by a thin layer of moisture.