What is the smallest unit of life that Cannot be broken down?

All living things are made of cells (Figure 3.3. 1); the cell itself is the smallest fundamental unit of structure and function in living organisms. (This requirement is why viruses are not considered living: they are not made of cells.

bio.libretexts.org - 3.3: A Cell is the Smallest Unit of Life - Biology LibreTexts

What is the 5 Ws strategy?

The five Ws (what, when, where, why, who) plus an H (how) strategy can be used in a variety of ways. It is often used to help students summarise an...

Last updated Jun 3, 2021

Why is my poop sticking to the toilet?

Sticky stool is usually a sign that your diet needs some adjustment — maybe a little less fat or some more water. But sticky stool can also be a...

Last updated Jul 9, 2021

Promotion

Levels of Organization of Living Things

Living things are highly organized and structured, following a hierarchy of scale from small to large (Figure (PageIndex{1})). The atom is the smallest and most fundamental unit of matter. It consists of a nucleus surrounded by electrons. Atoms combine to form molecules, which are chemical structures consisting of at least two atoms held together by a chemical bond. Many molecules that are biologically important are macromolecules, large molecules that are typically formed by polymerization (a polymer is a large molecule that is made by combining smaller units called monomers, which are simpler than macromolecules). An example of a macromolecule is deoxyribonucleic acid (DNA) (Figure (PageIndex{3})), which contains the instructions for the structure and functioning of all living organisms. In plants, animals, and many other types of organisms, molecules come together in specific ways to create structures called organelles (Figure (PageIndex{1})). Organelles are small structures that exist within cells and perform specialized functions. Examples of organelles include mitochondria and chloroplasts (Figure (PageIndex{5-8})), which carry out indispensable functions: mitochondria produce energy to power the cell, while chloroplasts enable green plants to utilize the energy in sunlight to make sugars. All living things are made of cells (Figure (PageIndex{1})); the cell itself is the smallest fundamental unit of structure and function in living organisms. (This requirement is why viruses are not considered living: they are not made of cells. To make new viruses, they have to invade and hijack the reproductive mechanism of a living cell; only then can they obtain the materials they need to reproduce.) Some organisms consist of a single cell and others are multicellular. Cells are classified as prokaryotic or eukaryotic. Prokaryotes are single-celled or colonial organisms that do not have membrane-bound nuclei; in contrast, the cells of eukaryotes do have membrane-bound organelles and a membrane-bound nucleus. Figure (PageIndex{1}). From an atom to the entire Earth, biology examines all aspects of life. (credit “molecule”: modification of work by Jane Whitney; credit “organelles”: modification of work by Louisa Howard; credit “cells”: modification of work by Bruce Wetzel, Harry Schaefer, National Cancer Institute; credit “tissue”: modification of work by “Kilbad”/Wikimedia Commons; credit “organs”: modification of work by Mariana Ruiz Villareal, Joaquim Alves Gaspar; credit “organisms”: modification of work by Peter Dutton; credit “ecosystem”: modification of work by “gigi4791″/Flickr; credit “biosphere”: modification of work by NASA) In most multicellular organisms, cells combine to make tissues (Figure (PageIndex{1})), which are groups of similar cells carrying out similar or related functions. Organs are collections of tissues grouped together performing a common function (Figure (PageIndex{1})). Organs are present not only in animals but also in plants. An organ system is a higher level of organization that consists of functionally related organs. For example vertebrate animals have many organ systems, such as the circulatory system that transports blood throughout the body and to and from the lungs; it includes organs such as the heart and blood vessels.

How much money does one person need to live their life?

How much money do you need to lead your “absolutely ideal life”? The answer for most people, according to new research by university psychologists,...

Last updated Oct 3, 2018

What was the first successful console?

the Magnavox Odyssey The first commercial video game console was the Magnavox Odyssey, developed by Ralph H. Baer and first released commercially...

Last updated Sep 27, 2018

Promotion

Organisms are individual living entities (Figure (PageIndex{1})). For example, each tree in a forest is an organism. Single-celled prokaryotes and single-celled eukaryotes are also considered organisms and are typically referred to as microorganisms. All the individuals of a species living within a specific area are collectively called a population (Figure (PageIndex{1})). For example, a forest may include many pine trees. All of these pine trees represent the population of pine trees in this forest. Different populations may live in the same specific area. For example, the forest with the pine trees includes populations of flowering plants and also insects and microbial populations. A community is the set of different populations inhabiting a common area (Figure (PageIndex{1})). For instance, all of the trees, flowers, insects, and other populations in a forest form the forest’s community. The forest itself is an ecosystem (Figure (PageIndex{1})). An ecosystem consists of all the living things in a particular area together with the abiotic, or non-living, parts of that environment such as nitrogen in the soil or rainwater. At the highest level of organization, the biosphere (Figure (PageIndex{1})) is the collection of all ecosystems, and it represents the zones of life on Earth. It includes land, water, and portions of the atmosphere.

bio.libretexts.org - 3.3: A Cell is the Smallest Unit of Life - Biology LibreTexts

What is the unhealthiest food in the world?

List of the Most Unhealthy Foods in the World Super-Sweet Cereals. Breakfast cereals are commonly loaded with sugar. ... Sugary Coffee Drinks. Many...

Last updated Jun 22, 2018

How do you treat water for long-term storage?

Liquid chlorine bleach (unscented) can be used to disinfect water for long-term storage. Use fresh chlorine bleach since it can lose up to half its...

Last updated Sep 7, 2019

Promotion

What stocks make money during war?

Top defense stocks Lockheed Martin. Lockheed Martin is the world's largest defense company and the U.S. government's biggest contractor. ......

Last updated Dec 10, 2019

Promotion

What's the longest you've gone without sleep?

264.4 hours In December 1963/January 1964, 17-year-old Gardner stayed awake for 11 days and 25 minutes (264.4 hours), breaking the previous record...

Last updated Jun 5, 2018