The first one and the fourth one
Answer:
Respiratory System: The respiratory system's main job is to move fresh air into your body while removing waste gases.
Nostril: To warm air on inhalation and remove moisture on exhalation.
trachea: Serves as passage for air, moistens and warms it while it passes into the lungs, and protects the respiratory surface from an accumulation of foreign particles.
bronchiole: To deliver air to a diffuse network of around 300 million alveoli in the lungs.
alveoli: To exchange oxygen and carbon dioxide molecules to and from the bloodstream during breathing.
pharynx: Helps the respiratory system by allowing air to make its way to the respiratory tract.
larynx: Produces vocal sounds and prevents the passage of food and other foreign particles into the lower respiratory tracts.
lungs: To help oxygen from the air we breathe enter the red cells in the blood.
ribs: To aid respiration and help protect the lungs.
diaphragm: Contracts and flattens when you inhale. Creates a vacuum effect that pulls air into the lungs, and relaxes when exhaling.
Answer:
Explanation:
When a substance has the capacity to disrupts the genetic compositions (DNA) of the organisms, to the extent that it makes the particular organism genetic materials prone to genetic mutation,( random changes in the genetic composition) such group of substances are called Mutagens.
ionizing radiation,radioactive decay are some examples of of physical mutagens, while biological mutagens examples include viruses and bacterial. Chemical mutagens are Benzene compounds,bromine,aromatic amines,sodium Azide.
They exerts their negative effects
by disrupting gene expression sequence of transcription, translation, or changed the nucleotides sequence of the DNA leading to deletion, addition, subtraction of genetic bases.Some may make chromosomes to be unstable, disrupting the structure
Although some mutagens can cause cancer, that is they are mutagens. not all mutagens carcinogenic.This is because the Mutagenic effects depends on the metabolites present in the cells of the organisms.
