Important Questions Test: Diversity in the Living World - Class 6 MCQ

Chickpea is classified as a dicotyledon because it contains two cotyledons, which are the two halves of the seed that store nutrients for the developing plant. In contrast, maize is a monocotyledon, characterized by having only one cotyledon. This distinction plays a significant role in plant classification and affects other traits, such as leaf structure and root systems. For example, dicots generally exhibit reticulate venation in their leaves, while monocots show parallel venation. Understanding these differences is essential for studying plant biology and agriculture.

Parallel venation is not present in the peepal tree.

Shrubs are defined by their woody stems that are typically shorter than trees and branch low to the ground. They are often found in gardens and landscapes, providing structure and habitat for various wildlife. An interesting fact about shrubs is that they can vary greatly in size and shape, and some, like the rose bush, produce beautiful flowers that attract pollinators such as bees and butterflies.

Trees are typically characterized by their tall height, brown and hard stems, and thick, woody stems. Thin branches are more commonly associated with shrubs and herbs. This distinction is important in understanding plant types as it helps in identifying their growth patterns and ecological roles. Interestingly, trees play a crucial role in the environment by providing oxygen, improving air quality, and supporting wildlife habitats.

Animals in cold regions have thick fur to trap heat and keep their bodies warm in extreme temperatures.

A pond is an aquatic habitat where plants and animals live in water. Other options represent terrestrial habitats.

The correct answer is:

d) They have soft, green stems that require support.

Explanation:

Climber plants (or climbing plants) have soft, flexible stems that cannot stand upright on their own. Instead, they rely on external support (like trellises, walls, or other plants) to grow upward by using tendrils, twining stems, or clinging structures.

Why not the other options?

• a) Incorrect – Climbers do not grow tall without support (that's more typical of trees or some shrubs).

• b) Incorrect – Thick, woody stems are a feature of trees and shrubs, not climbers.

• c) Incorrect – Climbers are not typically aquatic plants (though some water plants may climb, it's not their defining trait).

Key trait: Soft stems + need support to grow vertically. Examples include peas, ivy, and money plants.

The hardness and thickness of stems are significant criteria for grouping plants. Different plants exhibit variations in their stems, which can be hard or soft, thick or thin. This classification helps in understanding the structural adaptations of plants, which can influence their growth and survival in various environments. For instance, woody plants like trees have harder stems to support their height, while herbs have softer stems that allow for flexibility and easier growth in diverse conditions. Understanding these characteristics can also provide insights into the ecological roles that different plants play within their habitats.

The taproot system is characterized by one prominent main root that grows deeper into the soil, with smaller lateral roots branching off from it. This type of root system is advantageous for anchoring the plant securely and accessing deeper moisture and nutrients. An example of a plant with a taproot system is the mustard plant, which allows it to thrive in various soil conditions. Interestingly, many plants with taproots, such as carrots and dandelions, store nutrients in their main roots, making them not only vital for the plant's health but also beneficial for human consumption.

The tomato plant is classified as an herb due to its soft, green stems and relatively small size compared to shrubs and trees. Herbs are typically non-woody plants and can be used in cooking, medicine, and gardening. Fascinatingly, many herbs are known for their aromatic properties and are essential in culinary practices worldwide, enhancing flavors and providing health benefits.

The mango plant is classified as a tree because it has a tall height, a hard, thick, brown, and woody stem, with branches starting higher up on the stem, away from the ground. The tomato plant is an herb with soft, green stems, the rose plant is a shrub with many woody stems branching close to the ground, and lemongrass is a grass with thin, fibrous roots. Trees like mango support biodiversity by providing shade and fruits for animals.

Birds usually live in trees or on land, while fish live in water. Birds are adapted for flying and perching; fish have gills to breathe underwater.

Animals help pollinate and spread seeds; plants offer food and shelter. This balance supports healthy ecosystems.

Reticulate venation refers to the pattern of veins that form a network in certain leaves, such as those of the hibiscus plant. This structure helps in the distribution of nutrients and water throughout the leaf, enhancing its ability to photosynthesize effectively. Interestingly, plants with reticulate venation are often dicots, which are a major group of flowering plants.

Observing plants and animals helps us understand biodiversity—the variety of life in an area. This supports ecosystem health and balance.