BIOLOGY 1 Marks Question

Nitrogen as a nutrient element is highly mobile in plants. It can be mobilised from the old and mature parts of a plant to its younger parts.

True.

True.

All the mineral elements present in a cell are not needed by the cell. For example, plants growing near radioactive mining sites tend to accumulate large amounts of radioactive compounds. These compounds are not essential for the plants.

Magnesium.

Aeration is done to provide proper oxygen to plants through roots.

Auxin (IAA).

These are called structural elements because they are the components of biomolecules of the cell.

Azotobacter.

Few prokaryotes like Rhizobium, Anabaena and Nostoc contains the enzyme nitrogenase, needed for the biological nitrogen-fixation. Eukaryotes do not possess this enzyme, therefore are unable to fix nitrogen.

Carbon, oxygen, sulphur.

Alnus.

Inward movement of ions into the cell is called influx while outward movement of ions out of the cell is called eflux.

1. Synthesis of chlorophyll.
2. Formation of nodules in legumes.

Thiamin, biotin and coenzyme A.

1. Iron.
2. Zinc.

Boron.

Epidermis of young roots or epiblema.

Amides are translocated to other parts of plant through xylem vessels in the form of nitrogen rich compounds as they contain more nitrogen than the amino acids.

Manganese facilitates splitting of water into oxygen and hydrogen, which in turn are utilized to make glucose during photosynthesis.

Symbiosis (mutualism).

It is done by decomposition.

No, mineral deficiency is not responsible for etiolation because it is related to absence of light.

Nitrogenase and nitrate reductase.

Ferredoxin.

Carbon.

Xylem.

Rhizobium.

Azotobacter is free living bacteria in the soil. It helps some cereal crops like maize (Zea Mays) in nitrogen fixation. The farmer adds Azotobacter culture to the maize field for enhancing the nitrogen element in the soil by the process of biological nitrogen-fixation.

Coenzyme A, Biotin.

Yes, this is because, the calcium itself is the constituent of cell wall whose presence makes the cell wall to become rigid and hard.

My corrhiza is a mutualistic association between a fungus and a vascular plant. In this relationship, the fungus gets shelter and food and carries out nitrogen fixation for the benefit of the vascular plant.

Mineral elements are the one obtained from soil, e.g., potassium and magnesium. And the non-mineral elements are the one obtained from air and water, e.g. carbon and oxygen.

No, every mineral element present in a cell is not needed by the plant body because all of them are not essential to its survival because they are not directly involved in the composition of their body.

Phosphorus, magnesium, copper, (any one).

Iron and copper.

Nitrogen, magnesium, potassium and iron.

Cystenine and methionine.

Nitrogen is the element which is obtained from both mineral and non-mineral sources.

Essential elements are grouped under two main categories on the basis of the fact that different elements are required in different concentrations by the plants. Hence, are consided as macro (required in large amounts) and micronutrients (required in small amounts).

Azotobacter.

Carbon and Oxygen.

Niypn HIPS and Venus fly trap grow in soil that has little nitrogen. They obtain nitrogen from insect’s body. Being carnivores, these plants trap insects inside their leaves, secrete liquid to digest the insect and take nitrogen from insect’s body.

Nitrogen, potassium, magnesium.