Living Things: Characteristics of Organisms and Atom Structure

Living Things: Basic Units and Structures

LIVING THINGSAtom: smallest unit of an element E Nucleus Protons P IN P Electron E NNN E P P NeutronsMolecule: union of two or more atoms Water molecule hydrogen hydrogen oxygenCell: structural and functional unit of all living things a a a a a alamy alamy a a a a a a a o CE8PE7 www.alamy.com a alamy alamyTissue: a group of cells that form a structure 0 shutterstock Intercalated discs Nucleus Cardiac or striated involuntary muscle tissue. adipose cells nuclei cytoplasmic membraneOrgan: a structure made of several tissues that function together to perform a specific taskOrgan System: several organs working together to perform a function in the body Esophagus Stomach Large intestine Small intestineOrganism: a complex individual made of organ systems

Characteristics of Organisms

Organisms Acquire Materials and Use Energy

Characteristics of All Living Organisms1. Organisms acquire materials and use energy · Organisms acquire nutrients from consuming other organisms (heterotrophs) or from photosynthesis (autotrophs). . Food provides the nutrient molecules which give energy for all activities (movement, reproduction, synthesis of molecules).

Living Organisms Reproduce

2. Living organisms reproduce . Living organisms can only come from other living organisms. . DNA is replicated in the parent so that hereditary information is passed to the offspring. DNA polymerase DNA replication Original DNA Topoisomerase Lagging stand Okazaki fragment RNA primer Primase Helicase Parent DNA Leading stand

Living Organisms Respond to Stimuli

3. Living organisms respond to stimuli Organisms react to stimuli in their environment such as sounds, odours, chemicals.

Living Organisms Are Homeostatic

4. Living organisms are homeostatic . The internal environment of a living organism stays relatively constant. . For example, human body temperature only fluctuates a minimal amount during the day and night.

Living Organisms Grow and Develop

5. Living organisms grow and develop Living organisms grow, which means they become larger. Growth can also mean an increase in the number of cells. Living organisms also develop throughout their life, which means that the body undergoes changes, including growth, repair and ageing.

Living Organisms Adapt to Environment

6. Living organisms have the capacity to adapt . Living organisms all possess certain features that make them successful in their environment (adaptations). . Individuals that have better adaptations for a particular environment will live longer and have more offspring (Natural Selection).Which moth is likely to be more successful? The moths that "blend in" will be more likely to survive, so a higher frequency of those traits will be seen in the population. Evolution is the change in the genetic makeup of a species over time.