cells 2013 14
TRANSCRIPT
Cells
1.The cell is the basic unit of all living things.
“building blocks of life”
Common Characteristics2. Living things, or organisms, have
common characteristics.
Reproduce
Grow and Develop
Are organized
RespondTo the environment
Living Things
Are organized
Grow and
develop
Respond to the
Environment Reproduce
Needs Of Life3. Organisms cannot carry out life activities without a few necessities
Living Things Need
Energy
Materials
Living Space
Such as carbon dioxide, nitrogen, oxygen and water
4. Living things, or organisms, that are made of a SINGLE cell are called unicellular and are usually too small for you to see.
5. Most organisms you can see are made up of many cells and are more complex. Organisms made up of many cells are called multicellular .
6. The microscope led to the discovery of cells.
The Discovery of Cells
7. In 1665, Robert Hooke discovered cells by examining slices of cork under a microscope.
Robert Hooke saw cork cells like these.
8. In 1673, Anton van Leeuwenhoek looked at pond scum under the microscope and saw creatures he called animalcules or “little animals”.
Microscopic organisms like these live in pond water.
The Discovery of Cells Continued….
• In 1838, Matthias Schleiden concluded that all plants are made of cells.
• In 1839, Theodor Schwann concluded that all animals are made of cells.
• In 1858, Rudolf Virchow concluded that all cells come from existing cells.
Every living thing is made of one or more cells.
Cells carry out the functions needed to support life.
Cells come only from other living cells.
10. There Are Two Types of Cells
• Prokaryotic cells
• No nucleus
• No separate “compartment” for genetic information/DNA
• Ex: Bacteria
• Eukaryotic cells• Nucleus• Membrane-covered
organelles
• DNA located in the nucleus
• Ex: All other cells (plants, animals, fungi, protists)
Examples of Prokaryotic Cells(Bacteria)
Examples of Eukaryotic Cells
Animal Cells
Human Liver Cells
Fungi Cells
Plant Cells
Protist CellHeart Muscle Cells
What are the cell parts?
Three Main Parts of a Cell
11. Most cells have three main parts.They are the
-cell membrane -cytoplasm
-nucleus 12. Each of these main
cell parts has a special and important job to do.
Cell membrane
Nucleus
Cytoplasm
Cell Membrane 13. The cell membrane is a protective
covering that encloses the entire cell. Any material coming into or out of the cell must pass through the cell membrane.
14. The cell membrane has three important jobs.
1. protects the inside of a cell2. supports and gives a cell its
shape 3. controls the movement of
materials into and out of a cell.
A cell membrane surrounds each of these cells.
Cytoplasm
15. The cytoplasm is a gelatin-like material contained inside the cell membrane.
16. Most of the activities in the cell take place in the cytoplasm.
The cytoplasm is colored yellow in this photo.
Nucleus 17. Most cells have a nucleus and are called
eukaryotes. 18. The nucleus is the control center of a cell
and contains the genetic information. 19. The nucleus controls all the life
processes of a cell. 20. The nucleus also controls cell
reproduction. 21. The nucleus is separated from the cytoplasm by
the nuclear membrane.
The nucleus of a cell can be seen by using a microscope.
Nuclear Structures
22. Chromosomes are a coiled structure of DNA and protein that forms in the cell nucleus during cell division.
23. DNA contains the instructions for how the cell is supposed to function.
24. Nucleolus (a structure located inside the nucleus) – the place where ribosomes are made.
Organelles 25. A cell is like a factory.
• Each machine in a factory has a special job.
• The machines work together to keep the factory working.
26. The "machines" of a cell are its organelles.
• Organelles are small structures that are suspended in the cytoplasm.
27. Each organelle has a special job to do. •Organelles work to:
- produce energy- transport materials- get rid of waste
•Organelles keep the cell working properly.
Mitochondria
28. One kind of organelle is the mitochondrion.
29. Mitochondria are known as the "powerhouses" of the cell.
30. They release energy that the cell can use.
31. The energy is used by the cell to carry out its life processes.
Endoplasmic Reticulum
32. The endoplasmic reticulum is also known as the ER.
33. The endoplasmic reticulum is a very small network of tubes inside the cell.
34. The tubes are like a tiny highway or transportation system for the cell. Substances move along these tubes from one organelle to another.
Ribosome35. Ribosomes are small, rounded
structures located within the cell. 36. Ribosomes make proteins. 37. The proteins are needed for growth and
are involved in all cell processes. 38. Some ribosomes appear as small
bumps attached to the ER. 39. Not all ribosomes are attached to the
ER, some are scattered throughout the cytoplasm.
Golgi Bodies
40. Cells contain many flattened and folded sacs called Golgi bodies. (looks like a stack of pancakes)
41. The Golgi bodies are like a post office for the cell.
42. Proteins and other materials are sent to the Golgi bodies through the endoplasmic reticulum.
43. Then, the Golgi bodies package and distribute the materials to other parts of the cell. They also send materials to the outside of the cell.
Vacuoles44. The vacuoles of a cell are small storage spaces
in the cytoplasm.
45. Vacuoles store food, waste, and water.
46. Plant cells usually have one large vacuole, and
animal cells may have many small vacuoles.
Lysosomes
47. Lysosomes are the cleanup crew of the cell.
48. Lysosomes contain powerful chemicals that digest nutrient molecules in the cell.
49. When other organelles in the cell stop working properly, the lysosomes break down and recycle the old cell parts so they can be used again. The chemicals in the lysosomes only break down unhealthy cell parts.
Ribosome
Endoplasmic reticulum
Nucleus
Nuclear membrane
Cell membrane
Cytoplasm
Lysosome
Golgi body
Mitochondrion
How do plant and animal cells differ?
Animal Cell
Red Blood Cells
Model of a typical animal cell
Plant Cell
Model of typical plant cell Actual plant cell
1. Cell Wall• All plant cells have a cell
wall
• Animal cells do not have a cell wall
• The cell wall surrounds the cell membrane of a plant cell
• Cell walls are made of a hard material called cellulose
The cell wall has three jobs
• Protect the plant cell
• Gives the cell its shape
• Gives the plant cell support
2. Vacuoles
• The number and sizes of vacuoles are different in plant and animal cells
• Plant cells have only one or two large vacuoles
• Animal cells have many small vacuoles
• Plant cell vacuoles store most of the water in the cell
3. Chloroplasts• Most plant cells have organelles
called chloroplasts• They contain a material called
chlorophyll• Chlorophyll gives a plant its
green color• Plants use chlorophyll to make
food through a process called photosynthesis.
• Animal cells do not have chloroplasts or chlorophyll
What are levels of organization???
*Some organisms are made of only one cell!! These organisms are called unicellular.*Other organisms, like plants, animals, and fungi are made of many cells. These organisms are called multicellular.*Multicellular organisms have levels of organization……
Organization of Life
• Cells are the basic units of life.• Cells that work together to perform a
specific job in the body are called tissues.• A group of tissues that work together to
perform a specific job are called organs.• Organs that work together in groups are
called organ systems.• Organ systems come together to form an
organism that can live on its own.
In other words….
cells tissues organs organ systems organism