Learn: Characteristics of Living Things

Welcome!Welcome to this lesson on the characteristics of living things! We'll explore what makes organisms alive and the features they share. Let's get started!

What does it mean to be alive?Living organisms exhibit certain characteristics that distinguish them from non-living things. These include processes like nutrition, respiration, and reproduction, among others. Understanding these characteristics helps us identify and study life forms.

Key Characteristics of Living OrganismsAll living organisms share several important characteristics that are essential for their survival and reproduction. Let's explore each one:

NutritionNutrition is how living organisms obtain the nutrients they need to grow and survive. For example, plants make their own food through photosynthesis, while animals consume other organisms.

RespirationRespiration is the process by which organisms convert glucose into energy. This energy is stored in a molecule called ATP (adenosine triphosphate), which fuels various cell functions.

ExcretionExcretion is the removal of waste products from an organism's body. For example, humans excrete carbon dioxide through the lungs and urea through the kidneys.

ResponseResponse refers to how living organisms detect and react to changes in their environment. For instance, plants grow towards light, and animals respond to danger by moving away.

MovementMovement is the ability of an organism to change position. Animals move their bodies to find food or escape predators, while plants move by growing towards light and water sources.

Growth and DevelopmentGrowth is the increase in size and number of cells, while development refers to changes that occur as an organism matures, such as a seed becoming a mature plant.

HomeostasisHomeostasis is the ability of an organism to maintain a stable internal environment. For example, humans regulate their body temperature by sweating when it’s hot or shivering when it’s cold.

ReproductionReproduction is the process by which organisms produce offspring, ensuring the continuation of their species. It can be sexual, involving the fusion of gametes, or asexual, where offspring are genetically identical to the parent.

PathogensSome organisms, called pathogens, can cause diseases. Pathogens include bacteria, viruses, fungi, and protoctists. Viruses are not living organisms as they rely on host cells to reproduce.

Review Time!Great work! You've learned about the characteristics of living organisms. Let's test your understanding with some final questions.