Zoology: Solved Previous Year Question Paper for NCERT/ CBSE Class 12th Zoology Paper code (RKDO18 ……20304-Z) 

Question: What is the significance of “Lac”
Answer: “Lac” is short for the genus Lactobacillus. Many species of Lactobacillus are important in food production, as they are involved in the fermentation process to produce various dairy products, such as yogurt, cheese, and kefir. These bacteria also act as probiotics, providing health benefits to the consumer. Additionally, certain species of Lactobacillus are used in biotechnology to produce lactic acid and other compounds.

Zoology: Solved Previous Year Question Paper for NCERT/ CBSE Class 12th Zoology Paper code (HSEIIRKON1—-15321-A) 

Write a short note on ‘MTP’.
Answer: MTP (Mixed Tissue Proteins) are proteins found in multiple tissues of the body. These proteins are involved in various functions such as cell signaling, metabolism, and other cellular processes. They are also involved in the cell-to-cell communication network.

Zoology: Solved Previous Year Question Paper for NCERT/ CBSE Class 12th Zoology Paper code (SEIIRKO-13-81020-Q) 

Question: Define Fertilization. Briefly enlist the events that take place during Fertilization.
Answer: Fertilization is the fusion of a sperm cell and an egg cell to form a single cell that has genetic material from both the egg and the sperm.
Events that take place during Fertilization:
1. Sperm binds to the egg and penetrates its outer layer.
2. The sperm and egg nuclei fuse, forming a single nucleus.
3. The egg is activated and begins the process of cell division.
4. The zygote begins to divide into two cells, then four cells, and so on.
5. The zygote starts to travel down the fallopian tube towards the uterus.

Botany: Solved Previous Year’s Question Paper for NCERT/CBSE  Class 12th Botany Paper Code (RKDO18 —–20303-X)

Question: (i)What is primary productivity ?
(ii) Why does it vary in different ecosystems ?
(ii) State the relationship between gross and primary productivity.
Answer: (i) Primary productivity is the rate at which energy is converted into organic matter by living organisms such as plants within an ecosystem.
(ii) It varies in different ecosystems due to the availability of resources, environmental factors such as temperature and light intensity, and the presence of other organisms.
(iii) The relationship between gross and primary productivity is that gross productivity is the total amount of energy produced by an ecosystem, while primary productivity is the amount of energy converted into organic matter. Gross productivity is the sum of all primary production, as well as respiration processes such as decomposition and consumption.

Zoology: Solved Previous Year Question Paper for NCERT/ CBSE  Class 12th Zoology Paper code (HSEIIRKO– 13) 

What are Biosafety issues?
Ans: The steps taken to assure the safe use, handling, and disposal of biological materials are referred to as biosafety issues. These concerns include the safe handling of genetically modified organisms, the containment of potentially infectious agents in laboratory settings, and adequate biological waste disposal. It also entails safeguarding the environment, lab workers, and other people from potentially dangerous chemicals.

Zoology: Solved Previous Year Question Paper for NCERT/ CBSE  Class 12th Zoology Paper code (HSEIIRKO–1) 

Humans have been producing silk using the silkworm, an insect, for thousands of years. A luxurious material, silk is used to create a variety of products, including clothing, bedding, and drapes. The silkworm is a crucial insect for human prosperity as it gives silk producers a vital source of revenue and aids in the creation of jobs in the textile sector. Since the silkworm is a crucial link in the food chain, it also contributes to the preservation of biodiversity. Numerous birds and other animals consume silkworm larvae, providing a natural food source. The silkworm is a significant pest control tool since it also produces a pesticide that is naturally occurring. The silkworm is a beneficial insect that plays a significant role in human welfare.

Shark: Excretory System, Reproductive System, Nervous System, and, Sense Organs

The excretory system is closely related to the reproductive system. Males and females differ significantly in several key ways. A pair of opisthonephric kidneys, which are long, thin, highly vascularized strips of tissue that filter nitrogenous wastes from the blood, chiefly urea, make up the excretory system. The archinephric ducts are responsible for kidney drainage. The more caudal section of the archinephric duct also carries urea produced by the kidneys in males, whereas the cranial portion of the duct serves primarily a reproductive purpose. The female has smaller and shorter archinephric ducts. The two tiny auxiliary urinary ducts in males that drain into the urogenital sinus receive urine from the archinephric ducts. The male auxiliary urinary ducts and the archinephric ducts discharge into the urinary papilla, a little projection into the cloaca. In males, the urogenital papilla is another name for the urinary papilla. Materials from the digestive, reproductive, and excretory systems are delivered to the cloaca. Excretory waste leaves the cloaca and travels outside. A duct connects the rectal or digitiform gland to the big intestine. This tubular organ helps the dogfish maintain a healthy osmotic equilibrium in its bodily fluids by excreting extra sodium chloride.

Shark: Skeletal System, Muscular System, Digestive System, Respiratory System, and, Circulatory System

Sharks have a fairly simple muscle structure. The majority of the musculature is made up of huge, striated, segmented, V-shaped muscle groups termed myotomes, which are easily visible in a skinned shark. The exceptions to this rule are specific muscles that govern the jaws and particular fins. A connective tissue-based myoseptum divides individual myotomes from one another. Additionally, a horizontal septum divides them into dorsal and ventral groupings.

Shark: The External Anatomy, Head, Trunk, and Tail

Sharks occur in over 400 different varieties. Each type of shark has a distinct appearance, diet, and behavior. Sharks may be found in all four oceans on the planet. Some sharks can fit inside a fish tank, while others are smaller than a school bus. Sharks come in a wide range of hues. Their skin tone usually makes it easier for individuals to blend in with their surroundings. However, certain sharks that dwell in the ocean’s deepest regions have sections that light at night. While some sharks can survive in freshwater, most sharks dwell in saltwater. Sharks all have different characteristics that make them special or make them unique. Sharks are a type of fish. Sharks and common fish have several similarities as well as differences. The cartilage that makes up a shark’s skeleton. Bones make up the skeleton of fish. The tough, flexible material found in people’s ears and noses is cartilage. Sharks have gills, just like other fish. Fish breathe through their gills. People use their lungs to absorb oxygen from the air, unlike fish. Fish use their gills to draw oxygen from the water. Sharks and fish need water to pass over their gills to acquire enough oxygen. Most sharks need to swim in water with a very high current to keep the water moving.