Science 7 Quiz Part 2

Food is a source of energy because it provides the body with the necessary nutrients and calories to fuel its functions and activities. The process of digestion breaks down food into smaller molecules, such as carbohydrates, proteins, and fats, which are then converted into energy through cellular respiration. This energy is used for various bodily processes, including metabolism, movement, and maintaining body temperature. Without food as a source of energy, the body would not be able to perform its essential functions.

DNA is the correct answer because it stands for deoxyribonucleic acid. DNA is a molecule that contains the genetic instructions for the development and functioning of all living organisms. It is found in the nucleus of cells and is responsible for carrying and transmitting genetic information from one generation to the next.

Living things are called organisms because the term "organism" refers to any individual living entity that exhibits the characteristics of life, such as growth, reproduction, and response to stimuli. This term encompasses a wide range of living beings, including plants, animals, fungi, and microorganisms. By using the term "organisms," we can categorize and refer to all living things collectively, regardless of their specific characteristics or classification.

The correct answer is food because it is one of the four basic necessities of life. Food provides the nutrients and energy that our bodies need to function properly. Without food, humans and other living organisms would not be able to survive. Therefore, food is essential for sustaining life.

Producers are organisms that can produce their own food through photosynthesis. Most plants have the ability to convert sunlight, water, and carbon dioxide into glucose and oxygen, making them producers in the ecosystem. They play a vital role in the food chain by providing energy and nutrients to other organisms, such as decomposers and consumers.

The cells of most organisms are made up of approximately 70% water.

Multicellular organisms reproduce sexually because this method involves the fusion of gametes (sperm and egg) from two parents, resulting in offspring with genetic variation. This genetic diversity is advantageous for the survival of the species as it allows for adaptation to changing environments and increases the chances of offspring inheriting beneficial traits. Additionally, sexual reproduction promotes genetic recombination, which can lead to the elimination of harmful mutations and the creation of new combinations of genes.

Cells are the basic structural and functional units of all living organisms. They contain all the necessary materials, such as DNA, proteins, and organelles, that are required for the various life processes to occur. Cells are capable of carrying out functions like metabolism, growth, reproduction, and response to stimuli. They are the building blocks of life and are responsible for the organization and functioning of all living things.

Organisms use energy to perform various essential functions such as moving materials in and out of cells, building cells, and making or breaking down food. Energy is required for active transport processes that allow substances to move against their concentration gradient, enabling the cell to maintain homeostasis. Additionally, energy is necessary for cellular respiration, which is the process of converting food molecules into usable energy in the form of ATP. Without energy, these vital cellular processes would not be possible, hindering the organism's survival and overall functioning.

A mushroom is an example of a decomposer because it plays a vital role in breaking down dead organic matter, such as fallen leaves or dead animals, into simpler substances. Decomposers like mushrooms help in the recycling of nutrients back into the ecosystem, making them an essential part of the food chain. They obtain their energy by breaking down complex organic compounds, releasing nutrients that can be used by other organisms.

Single-celled organisms grow as the cell gets larger because they need to increase in size in order to accommodate the necessary cellular components and organelles. They reproduce asexually, meaning they can produce offspring without the need for a mate, which allows them to rapidly increase their population. Additionally, single-celled organisms do not have specialized cells that perform specific functions like multicellular organisms do. Instead, they rely on their single cell to perform all necessary functions for survival and reproduction.

Fish in very cold waters do not freeze because of a natural antifreeze- this is an example of homeostasis. Homeostasis refers to the ability of an organism to maintain a stable internal environment despite changes in the external environment. In this case, the fish have developed a mechanism to regulate their body temperature and prevent freezing in extremely cold waters, which is a form of maintaining homeostasis.

Cells are the basic building blocks of all living organisms. They are capable of performing various functions, and sometimes they become specialized to carry out specific tasks. Specialized cells have unique structures and functions that enable them to perform their designated roles more efficiently. These specialized cells can be found in different organisms, including plants, animals, and microorganisms, and they play a crucial role in maintaining the overall functioning of the organism.

Producers are organisms that are capable of converting sunlight into energy through the process of photosynthesis. They are able to synthesize their own food, usually in the form of carbohydrates, and are the primary source of energy for all other organisms in an ecosystem. In this context, humans can be considered as producers because they have the ability to cultivate plants and crops for food production.

Humans obtain water through their skin by absorbing moisture from the environment, such as through sweating or being in a humid environment. They also obtain water by drinking fluids, which is the most common and direct way to hydrate the body.