This worksheet will help you learn about the key characteristics that define living organisms. Use it to test your knowledge and deepen your understanding of biology.
Instructions: Read each question carefully and provide a concise and accurate answer. Use examples where appropriate.
What are the Characteristics of Living Things?
Before we delve into specific questions, let's review the main characteristics that distinguish living things from non-living things. These include:
- Organization: Living things exhibit a high degree of organization, from atoms to molecules, to cells, tissues, organs, organ systems, and finally, the organism itself.
- Metabolism: Living things carry out metabolic processes, which involve chemical reactions that provide energy and build or break down molecules.
- Growth and Development: Living things increase in size (growth) and change over time (development).
- Adaptation: Living things adapt to their environments through natural selection. This involves inheritable traits that increase survival and reproduction.
- Response to Stimuli: Living things react to changes in their internal or external environment (stimuli).
- Reproduction: Living things produce offspring, passing on their genetic information.
- Homeostasis: Living things maintain a stable internal environment despite changes in the external environment.
Frequently Asked Questions (FAQs) and Activities:
1. What is the difference between growth in living things and the increase in size of a crystal?
Growth in living things involves an increase in size and complexity due to the production of new cells and the organization of those cells into tissues and organs. This is a fundamentally different process from the simple increase in size of a non-living crystal, which is a result of the addition of more material to its existing structure without any internal organization or cell division.
2. Explain how a plant demonstrates response to stimuli.
Plants respond to stimuli such as light (phototropism), gravity (gravitropism), and touch (thigmotropism). For example, a plant's stem will grow towards a light source (positive phototropism), while its roots grow downwards due to gravity (positive gravitropism). A climbing plant's tendrils will wrap around a support structure when touched (positive thigmotropism).
3. Give an example of homeostasis in the human body.
The human body maintains a remarkably stable internal temperature of around 98.6°F (37°C). This is achieved through a variety of mechanisms, including sweating when it's hot and shivering when it's cold. This regulation of body temperature is a classic example of homeostasis.
4. How do single-celled organisms reproduce?
Single-celled organisms, like bacteria and amoeba, primarily reproduce asexually through processes like binary fission, where the cell divides into two identical daughter cells.
5. Provide examples of adaptations in living organisms.
Adaptations are numerous and varied. A desert cactus has spines to reduce water loss and a thick stem to store water. A polar bear has thick fur and blubber to stay warm in freezing temperatures. These are just a few examples of how organisms have adapted to their environments.
6. Explain how metabolism is essential for life.
Metabolism encompasses all the chemical processes within an organism that are necessary for sustaining life. These processes involve obtaining and utilizing energy from nutrients, building and breaking down molecules, and eliminating waste products. Without metabolism, an organism could not grow, repair itself, or reproduce.
Challenge Questions:
- Can a virus be considered a living thing? Explain your reasoning.
- Discuss the role of adaptation in the process of evolution.
- How does the concept of homeostasis relate to the survival of an organism?
This worksheet provides a framework for understanding the characteristics of life. Remember to consult your textbook or other resources for further exploration of these fascinating concepts.
