Biology Mock Test- 1 - Class 9 MCQ

Cell is kept in hypotonic solution then due to osmosis the solvent particles enter into the cell termed as endosmosis which results in bulging of the cell this state is termed as turgid cell.

Parthenium hysterophorus is a noxious weed in America, Asia, Africa and Australia. This weed is known to cause many health hazards which have now reached epidemic proportions. This weed is considered to be a cause of allergic respiratory problems, contact dermatitis, mutagenicity in human and livestock. Crop production is drastically reduced owing to its allelopathy. Also aggressive dominance of this weed threatens biodiversity. 

The practice of cultivating two or more crops simultaneously on the same piece of land is called mixed cropping. During mixed cropping, if one crop faces adverse conditions or pathogen attack then the other crop can be saved. Wheat and maize cannot be grown together as wheat is a rabi crop and maize is a kharif crop.

Nearly half of the bacteria are motile due to the presence of flagella. These are long, thin, helical appendages.

• Chromosome beasis genes present in nuclear region.

• Genes are contained in chromosomes, which are in the cell nucleus.

• A chromosome contains hundreds to thousands of genes.

• Every normal human cell contains 23 pairs of chromosomes, for a total of 46 chromosomes.

• A trait is any gene-determined characteristic and is often determined by more than one gene.

Prokaryotes lack nucleus and thus they are called nucleoid. 
Eukaryotes contain nucleus and thus they are referred as complete cell. 
Viruses act both as living and non- living. 
Peroxisomes helps in removal of toxic substances.

Tissue is a cellular organizational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues.

The three principal shapes associated with epithelial cells are - squamous, cuboidal and columnar. Squamous epithelium has cells that are wider than their height (flat and scale-like). This is found as the lining of the mouth, oesophagus, the blood vessels and in the alveoli of the lungs.

Mitochondria are called the power house of the cell because it contain enzyme for cellular respiration in which energy is released in form of ATP

The strict biological definition of a fish, above, is sometimes called a true fish. True fish are also referred to as finfish or fin fish to distinguish them from other aquatic life harvested in fisheries or aquaculture.

Blue Revolution refers to the time of intense growth in the worldwide aquaculture industry from the mid-1960s to present. Blue Revolution is an explosion in aquaculture, and specifically fish production as a form of self-sufficiency, nutrients, and economic growth for India.

The largest cell is ovum in the human body. The ovum also called egg cell is the reproductive cell in the female body. Ovum is 20 times bigger than the sperm cells and has a diameter of about 0.1 mm.

Leghorn is probably the best egg-laying breed to introduce to tropical Countries, if conditions are not too harsh. Eggs are produced at a lower price and the large comb and wattles, naked legs and white feathers are all factors favouring thermo-tolerance. Where a hot climate and insufficient feeding are limiting factors, Leghorn-derived breeds are more suitable and may also be utilised to improve  the genetic pool of local strains.

Breeder hen diets should be supplemented with Vitamin K to ensure good chick health. Laying hens fed a diet deficient in vitamin k produce eggs low in the vitamin, and when the eggs are incubated, the chicks produced have low reserves and a prolonged clotting time. Vitamin A  is easily destroyed in feed processing and storage. Usually, 10,000-15, 000 IU/ kg vitamin A is supplemented in broiler or broiler breeder commercial feed. High levels of vitamin A decreased egg production, size, and hatchability in laying hens.

A zebu or Bos indicus or Bos taurus indicus, sometimes known as indicine cattle or humped cattle, is a species or subspecies of domestic cattle originating in the Indian Subcontinent. Zebu are characterised by a fatty hump on their shoulders, a large dewlap, and sometimes drooping ears. They are well adapted to withstanding high temperatures, and are farmed throughout the tropical countries, both as pure zebu and as hybrids with taurine cattle, the other main type of domestic cattle.

The term protoplasm was coined by J.E Purkinje. Protoplasm is the fluid medium in which different cell organelles are present.

Nervous tissue is found in the brain, spinal cord and nerves. It is responsible for coordinating and controlling many body activities. It stimulates muscle contraction, creates an awareness of the environment, and plays a major role in emotions, memory and reasoning. So, nervous tissue helps in making quick decisions after analyzing.

Electron  microscope is used to understand the complex structure of the cell and its various organelles. when was it discovered.

Arerolar tissue is known as packaging tissue. It is a type of connective tissue andhas a lot of space inside it which stores fat. Areolar tissue fills up the spaces between skin and other tissues.

These are cells without a nucleus, such as erythrocytes (Red blood Cells) that have this property probably to give more space to carry more Haemoglobin. The Nucleus contains the DNA on which a couple of processes can be carried out such as transcription (gene copying in the form of mRNA) and translation (of the gene into an amino-acid sequence (polypeptide chain)) . Also, mitosis is nuclear division, starting by the replication of DNA. That's why erythrocytes do not undergo mitosis, but wear out and are replaced.Human red blood cells are an example of a non-nucleated cell.Non nucleated cells are cells which contain cytoplasm but no nucleus. They cannot reproduce themselves or divide.

Green manure is a term used to describe crops or plants which are grown for the purpose of manuring the soil. Green manure crops are grown, cut and ploughed in the soil to enhance the soil fertility. Green manuring is an eco-friendly method of manuring the soil. Examples of green manure crops include sunhemp, dhaincha etc.

Pusa Lerma was developed from the wheat category named  Lerma Rojo using  mutation breeding owing to the objection of farmers to use the wheat supplied having low market value by Mexico to India.

Collenchyma allows an individual to easily bend the stem of a plant without breaking it. 

It is uniquely located at the connection of the leaf. 

The unique feature of collenchyma is because of the presence of the elongated cells and strong irregular walls in its structure.

 Also, these cells provide additional support to the entire plant.