General Knowledge 7th Grade Test No.01

Fish breathe with gills instead of a nose because they live in water. Gills are specialized organs that allow fish to extract oxygen from water. They are located on the sides of the fish's head and are made up of thin, feathery structures called filaments. As water passes over the gills, oxygen is extracted from the water and absorbed into the fish's bloodstream, while carbon dioxide is released. This adaptation allows fish to efficiently extract oxygen from their aquatic environment, enabling them to survive and thrive underwater.

The part of plants that grows below the soil is called the root. The root is responsible for anchoring the plant in the ground and absorbing water and nutrients from the soil. It also stores food for the plant and helps in the process of reproduction. The stem, on the other hand, is the part of the plant that supports the leaves, flowers, and fruits. Plants and flowers are broader terms that encompass the entire plant or specific reproductive structures, respectively, and do not specifically refer to the part that grows below the soil.

Photosynthesis is not a part of plants, but rather a process that occurs within plants. It is the process by which plants convert sunlight, water, and carbon dioxide into glucose and oxygen. While photosynthesis is a vital function for plants, it is not a physical part or component of the plant itself like the leaf, stem, or root.

The claws and canine teeth of wild animals are sharp because they are used to hold and eat other animals. These sharp tools enable wild animals to catch and secure their prey, allowing them to tear through flesh and consume their food. This adaptation is essential for their survival as it helps them obtain the necessary nutrients from their prey.

Insectivores refers to animals or plants that primarily feed on insects. In this context, the question is asking for the name of plants that eat insects, so the correct answer is "Insectivores." Herbivores refers to animals that eat plants, autotrophic refers to organisms that produce their own food through photosynthesis, and symbiotic refers to a close and long-term interaction between different species.

Adaptations refer to the changes that occur in the body parts of an organism in order to adjust to their surroundings. These changes can be physical, physiological, or behavioral, and they help organisms survive and thrive in their specific environment. Through adaptations, organisms are able to better obtain food, avoid predators, reproduce, and withstand environmental conditions such as temperature, humidity, and availability of resources. Adaptations can occur over long periods of time through the process of natural selection, as well as through individual or population-level changes in response to immediate environmental changes.

Plants in forest regions grow very tall in order to compete for sunlight. Sunlight is a vital resource for plants as it is necessary for photosynthesis, the process by which plants convert sunlight into energy. In dense forest areas, sunlight is limited due to the dense canopy created by tall trees. Therefore, plants have evolved to grow tall so that they can reach above the canopy and receive sufficient sunlight for their survival and growth. By competing for sunlight, plants ensure their access to this essential resource and increase their chances of survival in the forest ecosystem.

The stem of desert plants are green because they perform photosynthesis. Photosynthesis is the process by which plants convert sunlight into energy, using chlorophyll in their stems and leaves. The green color of the stem indicates the presence of chlorophyll, which is necessary for photosynthesis to occur. This allows the plants to produce their own food and survive in the harsh desert environment where resources are limited.

Living things need nutrition for all of the above reasons. Nutrition provides the necessary energy and nutrients to fight diseases, support the growth of the body, and aid in the development of the body. Proper nutrition is essential for maintaining a healthy immune system, promoting physical growth, and ensuring the body's overall development.

Micro nutrients are the nutrients required in small quantities by the body. These include vitamins and minerals that are essential for proper functioning and maintenance of the body. Macro nutrients, on the other hand, are required in larger quantities and include carbohydrates, proteins, and fats. Foodstuffs is a general term that refers to any type of food. Therefore, the correct answer is micro nutrients.

Plants can produce their own food through a process called photosynthesis. Chlorophyll, which is present in the chloroplasts of plant cells, captures sunlight and converts it into chemical energy. This energy is then used to combine water and carbon dioxide to produce glucose, which is the plant's food source. Therefore, all the given options - chlorophyll, sunlight, and water - are necessary for plants to produce their own food.

The conical shape of deodar and pine plants helps to prevent heavy snowfall. The conical shape allows the snow to slide off the branches easily, reducing the weight on the branches and preventing breakage. This adaptation is important for the survival of the plants in regions with heavy snowfall, as it protects them from damage and allows them to continue growing and thriving.

Both macro and micro nutrients are types of nutrients. Macro nutrients are required in large quantities by the body and include carbohydrates, proteins, and fats. Micro nutrients, on the other hand, are required in smaller quantities and include vitamins and minerals. Therefore, the correct answer is "Both a and b" because both macro and micro nutrients are types of nutrients.

Grasses have fibrous roots that spread out horizontally in the soil, forming a dense network. This network of roots helps to bind the soil particles together, preventing them from being washed away by water or blown away by wind. Therefore, the fibrous roots of grasses play a crucial role in preventing soil erosion.

Heterotrophic nutrition refers to the type of nutrition in which organisms depend on other animals and plants for their food. Unlike autotrophic nutrition, where organisms can produce their own food through photosynthesis, heterotrophic organisms rely on consuming other living organisms or organic matter for their energy and nutrients. Therefore, the correct answer is heterotrophic nutrition.

The symptoms of food spoilage include skins turning black, foul odor, and bad odor. These signs indicate that the food has gone bad and is no longer safe to consume. The blackening of skins is often a visual indicator of spoilage, while foul and bad odors are caused by the growth of bacteria or other microorganisms on the food. Therefore, all of the given options are correct symptoms of food spoilage.

Internodes are the sections of a stem that are located between two nodes, which are the points where leaves, buds, or branches grow. The internodes are typically elongated and provide support and spacing between the nodes. They allow for the growth and development of the plant by providing space for new leaves or branches to emerge. Therefore, internodes are the correct term for the part of the stem between two nodes.

Autotrophic nutrition refers to the ability of certain organisms to produce their own food. These organisms, such as plants, are capable of synthesizing organic compounds using inorganic substances like carbon dioxide and sunlight through the process of photosynthesis. This enables them to sustain themselves without relying on external sources for nutrition. Animals, on the other hand, obtain their food by consuming other organisms, making them heterotrophic. Therefore, the correct answer in this case is Autotrophic nutrition.

The correct answer is "Both a and b" because food wastage can be categorized into two types: quantitative and qualitative. Quantitative food wastage refers to the physical amount of food that is discarded or lost, such as leftovers or expired products. On the other hand, qualitative food wastage refers to the loss of food quality, such as when food becomes spoiled or contaminated. Therefore, both types of food wastage contribute to the overall problem of food waste.

The atmospheric pressure is the force exerted by the weight of the air above a given point. Since the air molecules are constantly moving and colliding with each other and with objects, the pressure is distributed equally in all directions. Therefore, the atmospheric pressure is the same in all directions.

Aquatic plants have air spaces in their stems and leaves to help them float on water. These air spaces provide buoyancy and allow the plants to stay afloat. This adaptation is important for the survival of aquatic plants as it enables them to access sunlight and perform photosynthesis effectively. By floating on water, these plants can also disperse their seeds and reproduce successfully. Therefore, the presence of air spaces in the stems and leaves of aquatic plants is specifically for floating on water.

Plants that grow on the body of other plants are called parasitic. These plants obtain their nutrients and water from the host plant, often causing harm or even death to the host. They rely on the host plant for survival and are unable to produce their own food through photosynthesis, making them dependent on other plants for their sustenance.

Monocotyledonous seeds are those that do not divide into two equal parts. In monocots, the seed typically has only one embryonic leaf, known as a cotyledon, which remains undivided. This is in contrast to dicotyledonous seeds, which have two cotyledons that divide during development. Insectivores and herbivores are unrelated to seed division and therefore not the correct answer.

The correct answer is "Both a and b." Nitrogen fixation refers to the conversion of atmospheric nitrogen into a usable form by living organisms. Atmospheric nitrogen fixation occurs through natural processes such as lightning and high-energy reactions. Biological nitrogen fixation, on the other hand, is carried out by certain bacteria and other microorganisms that convert atmospheric nitrogen into ammonia or other nitrogen compounds. Therefore, both atmospheric and biological nitrogen fixation are types of nitrogen fixation.

The transport system of plants consists of the xylem system, which carries water and minerals to all parts of the plant. This is because water and minerals are essential for the growth and survival of plants. The xylem vessels in plants act like tiny pipes, transporting water and dissolved minerals from the roots to the leaves and other parts of the plant. Therefore, the correct answer is "Both a and b" as both water and minerals are transported through the xylem system.

The correct answer is "Less evaporation of water." Desert plants have adapted to their arid environment by modifying their leaves into thorns or needles. This modification reduces the surface area of the leaves, which in turn reduces the amount of water that can evaporate from the plant. This helps the plant conserve water in the desert where water is scarce.

Macro nutrients are the nutrients required by the body in large quantities for proper functioning. These include carbohydrates, proteins, and fats. Micro nutrients, on the other hand, are required in smaller quantities and include vitamins and minerals. Foodstuffs refer to any type of food. Therefore, the correct answer is macro nutrients as they are the nutrients required in large quantities.

The tip of the leaf is called the leaf apex. This term refers to the pointed or rounded end of the leaf. It is the opposite end of the leaf from the leaf base, which is where the leaf attaches to the stem. The leaf apex can vary in shape and may be used to identify different types of leaves.

Dicotyledonous refers to plants whose seeds have two cotyledons or embryonic leaves. These cotyledons store nutrients and provide energy for the seedling as it begins to grow. When the seed germinates, the cotyledons emerge and split into two equal parts. This characteristic distinguishes dicotyledonous plants from monotyledonous plants, which have only one cotyledon. Herbivores and insectivores, on the other hand, are not relevant to the division of seeds and do not describe this specific characteristic.

The frog and duck have webbed toes because they can use them like oars. This means that their webbed toes help them to paddle through the water more efficiently, allowing them to swim faster and navigate through their aquatic habitats with ease. The webbing between their toes increases the surface area, providing more resistance against the water and generating more propulsion. This adaptation is essential for their survival as it enables them to catch prey, escape from predators, and find mates in their watery environments.

Saprophytic plants obtain their food from dead animals or decaying organic matter. They break down the complex organic compounds present in dead animals and absorb the nutrients released during the process of decomposition. This allows them to survive and obtain the necessary nutrients without relying on photosynthesis or other means of obtaining energy from sunlight.

Plants convert light energy into chemical energy through the process of photosynthesis. During photosynthesis, plants use sunlight, carbon dioxide, and water to produce glucose (a type of sugar) and oxygen. The glucose is then converted into various forms of carbohydrates, such as starch, which are stored in different parts of the plant as food. Therefore, the correct answer is "Food" as plants store the chemical energy in the form of carbohydrates.

The stem is not part of the flower. The stem is the main structural part of a plant that supports the leaves, flowers, and fruits. It connects the roots to the rest of the plant and provides a pathway for water, nutrients, and sugars. The flower, on the other hand, is the reproductive structure of a plant, consisting of the calyx, corolla, and other parts involved in reproduction.

Plants that have leaves and stems covered with a waxy layer are typically found in water. The waxy layer, known as a cuticle, helps to prevent water loss and protect the plant from drying out in aquatic environments. This adaptation is necessary for plants living in water because they are constantly surrounded by a moist environment and need to retain water to survive. Additionally, the waxy layer also helps to repel excess water and prevent the plant from becoming waterlogged. Therefore, the presence of a waxy layer on the leaves and stems is a characteristic feature of plants that inhabit water.

The part that grows from inside the seed above the soil is called the plumule. The plumule is the embryonic shoot of a plant that develops into the stem and leaves. It is responsible for the upward growth of the plant and the production of foliage. Unlike the radical, which grows downward and develops into the root system, the plumule grows upwards towards the sunlight to support photosynthesis and overall plant growth.

The nutrition in which living things depend on each other is called "symbiotic nutrition." Symbiotic nutrition refers to a biological relationship in which two or more different species interact and depend on each other for their nutrition or survival. This relationship can take various forms, such as mutualism (both species benefit), parasitism (one species benefits at the expense of the other), or commensalism (one species benefits, and the other is neither helped nor harmed). Symbiotic interactions are common in ecosystems and play a crucial role in the balance of nature.

The radicle is the part of the plant embryo that grows from inside the seed towards the soil. It is the primary root of the plant and is responsible for anchoring the plant in the soil and absorbing water and nutrients. The stem, plumule, and leaves are all different parts of the plant, but they do not specifically grow from inside the seed towards the soil.

Simple leaves are characterized by having a single undivided leaf blade. This means that the leaf is not divided into smaller leaflets or lobes. Compound leaves, on the other hand, have a leaf blade that is divided into multiple leaflets. Unity and Complicated Leaves are not valid terms used to describe this type of leaf structure.

The correct answer is "Both a and b." The broad, spread-out part of the leaf is called the leaf blade or lamina. Both terms can be used interchangeably to refer to this part of the leaf. The leaf margin, on the other hand, refers to the edge or border of the leaf.

The transport system of plants, known as the phloem system, is responsible for supplying food to all parts of the plant. This system transports the sugars produced during photosynthesis, such as glucose, to various parts of the plant where they are needed for growth, energy production, and storage. The phloem system consists of specialized cells called sieve tubes that form a network throughout the plant, allowing for the efficient distribution of food molecules. Therefore, the correct answer is "Food."