Application Of The Principles Of Heredity

(a)(i) What is an ecological niche?

 (i) State five roles played by a mango tree in its ecological niche.

(b)i) State two reasons why ecologists use sampling techniques in population studies.

(i) State four examples of sampling techniques used in population studies.

(c)Name four types of fingerprints in humans.

(d)) Name the plant used by Gregor Mendel in his experiment.

(ii) State two reasons why the plant named in 3(d) was used.

Maelezo ya Majibu

(a) Ecological niche: An ecological niche refers to the specific role and position that an organism occupies within an ecosystem. It includes the interactions and relationships of the organism with its environment, including other organisms, resources, and physical factors. Essentially, the ecological niche describes how an organism fits into its ecosystem and the functions it performs within that system. (i) Roles played by a mango tree in its ecological niche: 1. Primary producer: Mango trees are photosynthetic organisms, converting sunlight into chemical energy through photosynthesis. They produce organic compounds (such as sugars) using carbon dioxide, water, and sunlight. 2. Habitat provider: Mango trees provide shelter and habitat for various organisms such as birds, insects, and small mammals. They offer nesting sites, food sources, and protection from predators. 3. Oxygen producer: Through photosynthesis, mango trees release oxygen into the atmosphere, contributing to the oxygen supply necessary for many organisms to survive. 4. Food source: Mango trees bear fruit, which serves as a food source for animals, including humans. The fruits provide nourishment and contribute to the diet and survival of many organisms. 5. Soil stabilization: The roots of mango trees help prevent soil erosion by binding the soil particles together, reducing the risk of landslides and maintaining the stability of the surrounding environment. (b) Ecologists use sampling techniques in population studies for two main reasons: (i) Reasons for using sampling techniques in population studies: 1. Practicality: It is often impossible or impractical to study an entire population due to factors such as time, cost, or logistics. Sampling allows ecologists to gather data from a representative subset of the population, providing insights into the larger population as a whole. 2. Accuracy: When properly designed and executed, sampling techniques can provide accurate and reliable information about a population. By collecting data from a well-selected sample, ecologists can make inferences and draw conclusions about the population with a reasonable level of confidence. (i) Examples of sampling techniques used in population studies: 1. Random sampling: This involves randomly selecting individuals from the population, ensuring that each member has an equal chance of being chosen. It helps to avoid bias and provides a representative sample. 2. Stratified sampling: This technique involves dividing the population into subgroups or strata based on specific characteristics and then randomly selecting individuals from each subgroup. It ensures representation from different groups within the population. (c) Types of fingerprints in humans: The four main types of fingerprints in humans are: 1. Loop: This type of fingerprint forms ridges that enter from one side, curve, and exit from the same side. It resembles a loop shape. 2. Whorl: Whorl fingerprints have ridges that form circular or spiral patterns. They have at least one ridge that makes a complete circuit. 3. Arch: Arch fingerprints have ridges that enter from one side and exit from the other side, forming a slight rise in the center. They do not make loops or circles. 4. Composite: Composite fingerprints are a combination of two or more of the above types. They may exhibit characteristics of both loop and whorl, or loop and arch patterns. (d) The plant used by Gregor Mendel in his experiment: The plant used by Gregor Mendel in his experiments on inheritance and genetics was the garden pea plant, scientifically known as Pisum sativum. (ii) Reasons why the garden pea plant was used: 1. Easy to cultivate: The garden pea plant is relatively easy to grow and cultivate, allowing for large-scale experiments and the controlled breeding of different varieties. 2. Observable traits: The garden pea plant exhibits distinct and easily observable traits, such as flower color (purple or white), seed shape (round or wrinkled), and plant height (tall or short). These traits