Name: key traits shared by living things
Uploaded: 2026-06-05T17:49:07.446Z
Duration: 1 min 23 s
Channel: JoVE

K12 Standards

Pennsylvania State Academic Standards

9-12

Life Science

Structure and Function

3.1.9-12.B

Characteristics of Life

Biology is the scientific study of life, where all living organisms share a few key characteristics.
 
 The biological world has a highly organized and complex structure, from molecules inside each cell to the organ systems that make up an organism&#x27;s body.
 
 Organisms can reproduce to create offspring, which together form a population.
 
 Their inherited genetic material provides instructions for growth and development, and small differences in this genetic material create variation among individuals.
 
 They also show behaviors in response to the environment, such as burrowing during the day to stay cool in the desert.
 
 Organisms regulate environmental interactions through both behavior and internal physiological processes. For instance, vascular regulation controls blood and heat flow in the ears of a desert hare.
 
 These processes use chemical energy from food, which transforms into kinetic energy to perform work, such as running away from predators.
 
 Over many generations, the interaction between environmental pressures and genetic variation allows populations to evolve through adaptation.
 
 We can see this in populations that evolved long ears and slim bodies in hot deserts, and short ears and large bodies in cold Arctic regions.

什么是生物学？

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Biology is a natural science that studies life and living organisms, including their structure, function, development, interactions, evolution, ...

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Education

教育

JoVE Core

Biology

生物学

Plant Biology

植物生物学

Diversity, Classification & Evolution

多样性、分类与进化

KEY TERMS AND CONCEPTS

关键术语与概念

key traits shared by living things

Biology studies life and living organisms. It looks at their structure, function, development, interactions, evolution, distribution, and taxonomy. The field is broad and includes anatomy, physiology, ethology, genetics, and other specialized branches.

Living things share several key traits. They are made of cells, contain heritable genetic material, can adapt and evolve, use metabolism to manage energy, interact with their environment, maintain homeostasis, reproduce, and grow and change. These traits help scientists recognize life across many different organisms.

Cellular organization is one of the clearest signs of life. Cell theory states that living organisms are made of one or more cells. The cell is the basic unit of life, and new cells come from cells that already exist. Even single-celled organisms, such as bacteria, can perform essential life functions through their structures and chemical reactions.

In multicellular organisms, cells do not work alone. They join to form tissues, organs, organ systems, and complete organisms. This organization can also be extended to populations, communities, ecosystems, and the biosphere.

Genetic material acts like a biological blueprint. DNA is passed from parents to offspring, and the environment shapes that material over many generations. This process is called adaptation. Natural selection is the process in which inherited traits improve survival and reproduction, and it is the central mechanism of evolution. A kangaroo rat shows this idea by burrowing into cooler soil and lowering its metabolic rate in hot, dry areas to reduce water loss.

Living things also must interact well with their surroundings. They search for resources and potential mates, and they regulate internal conditions at the same time. Homeostasis is the ability to keep those internal conditions steady. Humans do this by shivering when cold and sweating when hot.

Metabolism is another major feature of life. It includes the chemical processes that regulate energy needs. Plants, for example, convert sunlight into sugar and store chemical energy in adenosine triphosphate.

These basic ideas support more advanced biology. Understanding cell division and replication helps scientists investigate larger questions, including what causes cancer. It also gives researchers the tools and methods they need to study biological processes.

Key Traits Shared by Living Things

characteristics of life

Biology studies life and living organisms. It looks at their structure, function, development, interactions, evolution, distribution, and taxonomy. The field is broad and includes anatomy, physiology, ethology, genetics, and other specialized branches. Living things share several key traits. They are made of cells, contain heritable genetic material, can adapt and evolve, use metabolism to manage energy, interact with their environment, maintain homeostasis, reproduce, and grow and change.

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levels of organization

Biological Hierarchy from Atoms to Biosphere

Biological organization describes how living things are arranged from the smallest parts to the largest Earth system. Each level adds complexity and builds on the level before it. The hierarchy begins with atoms and ends with the biosphere. Atoms are the smallest units of ordinary matter. They contain a nucleus and electrons. Two or more atoms held together by chemical bonds form molecules, and those bonds are often covalent, ionic, or metallic. Biomolecules are molecules found in living...

taxonomy

Taxonomy and Biological Naming

Taxonomy is the system scientists use to classify and name living organisms by shared traits. It organizes life into a series of ranked groups that use Latin names. The smallest taxonomic units are genus and species, and these two levels are used to give each organism a formal name. This naming system is called binomial nomenclature, and Carolus Linnaeus formalized it in the 18th century. Linnaeus’s hierarchy is still used today, although it has been expanded. From the broadest group to the...

phylogeny

Phylogenetic Trees and Evolution

Phylogenetic trees show how organisms are related through evolution. They map the diversification of organisms or groups of organisms over time. In biology, a named group is called a taxon, and the plural is taxa. Taxa can be broad or narrow. They may include all birds, which form the class Aves, or a smaller group such as all species of daisies in the genus Bellis. A phylogeny can focus on one genus or cover an entire kingdom. It is usually shown as a branching diagram called a phylogenetic...

key terms and concepts

Explore the traits that define life, from cells and DNA to homeostasis, metabolism, adaptation, and natural selection, in this high school biology lesson.

Key Traits Shared by Living Things | JoVE K12

JoVE Core series brings biology to life through over 300 concise and easy-to-understand animated video lessons that explain key concepts in biology, plus more than 150 scientist-in-action videos that show actual research experiments conducted in today’s laboratories.

biology

JoVE Core系列通过300多节动画视频课简明易懂地讲解生物学中的关键概念，以及150余段视频展示科学家在现代实验室开展实际研究实验，让生物学变得平易近人。

Louisiana Student Standards for Science

High School

Life Sciences

from-molecules-to-organisms-structures-and-processes

From Molecules To Organisms: Structures And Processes

HS-LS1-2

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

Human Anatomy and Physiology

Levels Of Organization

Hierarchy of Organization

Tennessee Academic Standards

From Molecules to Organisms: Structures and Processes

BIO1.LS1.1

Virginia  Standards of Learning

HIgh School

BIO.6

BIO.6.a

Earth Science

ES.3

ES.3.a

LS.3

LS.3.a

Minnesota Academic Standards in Science

2.2.1 9L.2.2.1.2

new-jersey-student-learning-standards-for-science

New Jersey Student Learning Standards for Science

Florida Department of Education

SC.912.L.14

SC.912.L.14.1

south-carolina-college-and-career-ready-science-standards

South Carolina College and Career Ready Science Standards

B-LS1-2.

new-york-state-science-learning-standards

New York State Science Learning Standards

HS-LS1-1.

Georgia Standards of Excellence

SB6.c

Next Generation Science Standards

ecosystems-interactions-energy-and-dynamics

Ecosystems: Interactions, Energy, and Dynamics

HS-LS2-6

Earth and Space Science

Earth’s Systems

HS-ESS2-6

HS-LS1-3

HS-LS1-1

What are Cells?

Cells are the smallest and basic units of life, whether it is a single cell that forms the entire organism, e.g., in a bacterium or trillions of them, ...

Cell Size

Cell sizes vary widely among and within organisms. Bacterial cells range between 1-10 micrometers (&#x3BC;m)and are considerably smaller than most ...

Eukaryotic Compartmentalization

One of the distinguishing features of eukaryotic cells is that they contain membrane-bound organelles, such as the nucleus and mitochondria, that carry ...

Prokaryotic Cells

Prokaryotes are small unicellular organisms that include the domains&#x2014;Archaea and Bacteria. Bacteria include many common organisms, such as ...

Cytoplasm

The cytoplasm consists of organelles and a framework of protein scaffolds called the cytoskeleton suspended in an aqueous solution, the cytosol. The ...

The Nucleus

The nucleus is a membrane-bound organelle that acts as a control center in a eukaryotic cell. It contains chromosomal DNA, which controls gene expression ...

Endoplasmic Reticulum

Endoplasmic ReticulumThe endoplasmic reticulum (ER) is an extensive network of membranous sacs and tubules in eukaryotic cells, continuous with the outer ...

Ribosomes

Ribosomes translate genetic information encoded by messenger RNA (mRNA) into proteins. Both prokaryotic and eukaryotic cells have ribosomes. Cells that ...

Golgi Apparatus

As they leave the Endoplasmic Reticulum (ER), properly folded and assembled proteins are selectively packaged into vesicles. These vesicles are ...

Lysosomes

Lysosomes are membrane-enclosed spherical sacs derived from the Golgi apparatus. The most important function of the lysosome is degrading macromolecules ...

Peroxisomes

Peroxisomes and mitochondria are two important oxygen-utilizing organelles in eukaryotic cells. Mitochondria carry out cellular respiration&#x2014;the ...

Introduction to the Cytoskeleton

Overview of the Cytoskeleton
The cytoskeleton is a network of protein filaments present within the cell, having three distinct filaments ...

Introduction to Actin

Actin is a highly conserved cytoskeletal protein found abundantly in eukaryotic cells. It constitutes 10% weight of the total cellular protein in muscle ...

overview-of-myosin-structure-and-function

Overview of Myosin Structure and Function

Myosins are a family of molecular motor proteins, first identified in the skeletal muscles, where they are responsible for muscle contraction. Along with ...

Microtubules

Microtubules are the thickest cytoskeletal filaments with a diameter of 25 nm. In prokaryotic organisms, microtubules are commonly found in locomotory ...

The Structure of Intermediate Filaments

The intermediate filaments are one of three widely studied cytoskeletal filaments. They are so named as their diameter (10 nm) is in between that of ...

Types of Intermediate Filaments

The intermediate filaments are an essential component of the cytoskeleton. Presently six types of intermediate filament have been identified. Type I and ...

Gap Junctions

Multicellular organisms employ a variety of ways for cells to communicate with each other. Gap junctions are specialized proteins that form pores between ...

The Extracellular Matrix

In order to maintain tissue organization, many animal cells are surrounded by structural molecules that make up the extracellular matrix (ECM). Together, ...

Tissues

Cells with similar structure and function are grouped into tissues. A group of tissues with a specialized function is called an organ. There are four main ...

Plant Cell Wall

The plant cell wall gives plant cells shape, support, and protection. As a cell matures, its cell wall specializes according to the cell type. For ...

Plasmodesmata

The organs in a multicellular organism&#x2019;s body are made up of tissues formed by cells. To work together cohesively, cells must communicate. One way ...

Cell Structure

Background
Cells represent the most basic biological units of all organisms, whether it be simple, single-celled organisms like bacteria, or large, ...

Visualizing Onion and Cheek Cells
ExpandImmediately before the experiment, wash and peel onion bulbs for the class.
Remove the entire brown outer skin and ...

Genomic DNA in Prokaryotes

The genome of most prokaryotic organisms consists of double-stranded DNA organized into one circular chromosome in a region of cytoplasm called the ...

Binary Fission

Fission is the division of a single entity into two or more parts, which regenerate into separate entities that resemble the original. Organisms in the ...

Genomic DNA in Eukaryotes

Eukaryotes have large genomes compared to prokaryotes. To fit their genomes into a cell, eukaryotic DNA is packaged extraordinarily tightly inside the ...

The DNA Helix

Overview

Deoxyribonucleic acid, or DNA, is the genetic material responsible for passing traits from generation to generation in all organisms and most ...

DNA as a Genetic Template

Two structural features of the DNA molecule provide a basis for the mechanisms of heredity: the four nucleotide bases and its double-stranded nature. The ...

DNA Packaging

Overview

Eukaryotes have large genomes compared to prokaryotes. In order to fit their genomes into a cell, eukaryotes must pack their DNA tightly inside ...

Organization of Genes

Overview

The genomes of eukaryotes can be structured in several functional categories. A strand of DNA is comprised of genes and intergenic regions. ...

Chromosome Structure

A functional eukaryotic chromosome must contain three elements: a centromere, telomeres, and numerous origins of replication.
The centromere is a DNA ...

The Central Dogma

The central dogma explains the flow of genetic information from DNA nucleotides to the amino acid sequence of proteins.
RNA is the Missing Link Between ...

Mutations

Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental factors. Mutations ...

Proteins: From Genes to Degradation

Students who demonstrate understanding can construct an explanation based on evidence for how the structure of DNA determines the structure of proteins which carry out the essential functions of life through systems of specialized cells.  Assessment Boundary: Assessment does not include the identification of specific cell or tissue types, whole body systems, specific protein structures and functions, or the biochemistry of protein synthesis.

3.1.9-12.A

Levels of Organization

Biological organization is the classification of biological structures, ranging from atoms at the bottom of the hierarchy to the Earth&#x27;s biosphere. ...

Taxonomy

Taxonomy is the science of defining and naming groups of biological organisms based on shared characteristics. It uses a hierarchy of increasingly ...

Phylogeny

Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon ...

Students who demonstrate understanding can develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.  Assessment Boundary: Assessment does not include interactions and functions at the molecular or chemical reaction levels.

Functions of Life

Human life is characterized by a variety of functions that are essential for survival and well-being. These functions include metabolism, movement, ...

Requirements for Human Life

The Earth and its atmosphere have provided humans with air, water, and food, but these are not the only requirements for survival. Humans also require a ...

What is Homeostasis?

Maintaining homeostasis requires that the body continuously maintain its internal conditions. Each physiological condition has a particular set point, ...

Negative and Positive Feedback

Homeostatic Imbalance

Homeostasis is the maintenance of a stable internal environment within the body, which is crucial for the proper functioning of cells, tissues, organs, ...

Students who demonstrate understanding can plan and conduct an investigation to provide evidence that feedback mechanisms maintain homeostasis.  Assessment Boundary: Assessment does not include the cellular processes involved in the feedback mechanism.

3.1.9-12.C

Key Traits Shared by Living Things

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