Answer:
The correct answer is option a. "Double-stranded regions of RNA typically take on an B-form right-handed helix".
Explanation:
Most of the native double-stranded DNA is on an B-form right-handed helix, following the structure proposed by Watson and Crick with about 10–10.5 base pairs per turn. However, double-stranded RNA does not follow this structure, and most regions have an A-form structure. The A-form right-handed helix have slightly more base pairs per turn, which makes it 20-25% shorter than B-DNA.
Answer:
Option C
Explanation:
Option A is incorrect as mutations may be detrimental to the organism and are not always beneficial. Option B is incorrect as there are instances where mutations may enable organisms to be better adapted to the environment. Option D is incorrect as genotypes are not selected for or selected against by environmental pressures, it is only the phenotype (exhibitable/ visible traits) that can be selected for or against, hence option C is the answer.
Answer:
the Echinoderms.
Explanation:
Examples of echinoderms: starfish, sea urchin, feather stars and sea cucumbers.
Answer:
Lung disease is any problem in the lungs that prevents the lungs from working properly. There are three main types of lung disease:
Airway diseases -- These diseases affect the tubes (airways) that carry oxygen and other gases into and out of the lungs. They usually cause a narrowing or blockage of the airways. Airway diseases include asthma, COPD and bronchiectasis. People with airway diseases often say they feel as if they're "trying to breathe out through a straw."
Lung tissue diseases -- These diseases affect the structure of the lung tissue. Scarring or inflammation of the tissue makes the lungs unable to expand fully (restrictive lung disease). This makes it hard for the lungs to take in oxygen and release carbon dioxide. People with this type of lung disorder often say they feel as if they are "wearing a too-tight sweater or vest." As a result, they can't breathe deeply. Pulmonary fibrosis and sarcoidosis are examples of lung tissue disease.
Lung circulation diseases -- These diseases affect the blood vessels in the lungs. They are caused by clotting, scarring, or inflammation of the blood vessels. They affect the ability of the lungs to take up oxygen and release carbon dioxide. These diseases may also affect heart function. An example of a lung circulation disease is pulmonary hypertension. People with these conditions often feel very short of breath when they exert themselves.
Explanation:
Put it your own words cause this is kinda advance for 7th
