1.1C THE CELL IS THE BASIC UNIT OF LIVING THINGSMiss Curd

7th Grade Science

ANSWER THE FOLLOWING Summarize the four characteristics of life Describe the three basic needs of all living

things What is the smallest unit of a living thing? Explain the difference between Unicellular

and Multicellular organisms How did the invention of the microscope lead

to the discovery of cells? What is the cell theory What did Louis Pasteur discover and what did

he develop as a result? What is spontaneous generation? Is it a valid

theory? Why or why not

LIVING THINGS VS. NON LIVING THINGS

What makes a living thing different from a non living thing?

There are 4 characteristics of life Organization

How is the body organized? The ability to develop and grow The ability to respond to the environment The ability to reproduce

WHAT DO LIVING THINGS NEED TO SURVIVE?

3 basic needs: Energy

Where does the energy come from? Plants use the Sun directly Animals use food from plants or other organisms

that eat the plants Materials

What kind of materials to organisms need? Carbon Dioxide, nitrogen, oxygen and water Where does most of this come from?

Food

Space to live and grow What happens if any of these requirements are

missing?

WHAT ARE LIVING THINGS MADE OF?

Cells: smallest unit of a living thing Organisms can be unicellular or

multicellular……..what’s the difference? Unicellular: made of a single cell and to small to see Multicellular: made up of many cells, each having a

different function What is the difference between the needs and

characteristics of a unicellular organism and a multicellular organism? All have the same needs and characteristics Unicellular: one cell carries out all of the activities

for life Multicellular: cells are specialized to do different

jobs

THE IMPORTANCE OF THE MICROSCOPE

Instrument that makes an object appear bigger than it is

First came into use in the 1600’s Robert Hooke and Anton van Leeuwenhoek

were some of the first to describe cells Hooke named the cell after looking at bark cells Van Leeuwenhoek described the cell after

looking at pond water

DO ALL LIVING THINGS HAVE CELLS?

Scientists started studying samples from various forms of living matter

Found cells in all of them Not all were exactly the same

Saw that living cells divide All of these findings led to the Cell Theory

1. Every living thing is made of one or more cells2. Cells carry out the functions needed to support

life3. Cells come only from other living cells

What is a theory?

OTHER IMPORTANT SCIENTISTS

Matthais Schleiden concluded that all plants are made of cells

Theodor Schwann concluded that all animals are made of cells

Rudolf Virchow concluded that all cells come from other cells

LOUIS PASTEUR Showed cell theory in the real world

Microscopic organisms are a cause of both spoilage of food and disease

Experiments showed that microscopic organisms (bacteria) were present in milk causing it to sour Developed a process of pasteurizations using heat to kill bacteria

Started to wonder if these also caused illness in humans and animals

Led to treatment of rabies in humans Disproved theory of spontaneous generation: the

belief that bacteria grew from nonliving things