Oxygen-poor blood enters the heart through the right atrium. From there blood flows through the tricuspid valve into the right ventricle. When the heart contracts during the diastolic phase, this blood is pumped out through the pulmonary arteries that run toward the lungs. At the lungs, the blood is circulated through a series of progressively smaller arterioles until it flows through capillaries lining the lungs' alveolar sacs. It is here that gas exchange takes place as oxygen is taken up by the blood, and carbon dioxide is released into the waste air.After oxygenation, the fresh blood is circulated back through the bronchial veins and into the pulmonary veins. These run from the lungs and drain into the heart's left atrium. During the systolic phase of the heartbeat, the mitral valve under the left atrium opens and permits blood to pass into the left ventricle. This chamber is heavily muscled and it has the power to pump the oxygen-rich blood out through the aorta and into the rest of the body.
Answer:
The gametophyte is green and nutritionally independent in mosses, liverworts, and fern.
Explanation:
The gametophyte is the sexual stage of growth in plants and algae.
During this stage, there is production of reproductive organs which produce sex cells.
During this stage, the gametophyte is independent since it relies fully on itself for food production.
The presence of chlorophyll enables this independence.
The gametophyte produces its own food through photosynthesis.
Answer:
X linked inheritance is one of the mechanisms of the inheritance which is associated with the mutation of the gene present on the X chromosome.
The characteristics of the X linked recessive inheritance that must be observed in the pedigree analysis will be-
1. X linked trait is always passed from the mother to the sons (females to males)
2. The males (XY) are usually affected by the gene as only one copy of the recessive gene in males can show its effect.
3. Females are the carrier of the disease but they are not affected by the condition.
