chapter 3 cell structure and function chapter preview 3.1 discovering cells 3.2 looking inside cells...
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Chapter 3 Cell Structure and Function
Chapter Preview
3.1 Discovering Cells
3.2 Looking Inside Cells
3.3 Chemical Compounds in Cells
3.4 The Cell In Its Environment
Table of Contents
Chapter 3 Cell Structure and Function
Chapter Preview Questions
1. In a microscope, an image is focused by
a. the eyepiece lens and the mirror.
b. the objective lens and the mirror.
c. the eyepiece lens and the objective lens.
d. the objective lens and a concave lens.
Chapter 3 Cell Structure and Function
Chapter Preview Questions
1. In a microscope, an image is focused by
a. the eyepiece lens and the mirror.
b. the objective lens and the mirror.
c. the eyepiece lens and the objective lens.
d. the objective lens and a concave lens.
Chapter 3 Cell Structure and Function
Chapter Preview Questions
2. An electron microscope uses a beam of electrons
instead of
a. slides.
b. lenses.
c. mirrors.
d. light.
Chapter 3 Cell Structure and Function
Chapter Preview Questions
2. An electron microscope uses a beam of electrons
instead of
a. slides.
b. lenses.
c. mirrors.
d. light.
Chapter 3 Cell Structure and Function
Chapter Preview Questions
3. Cells break down carbohydrates to get ____ for life processes.
a. energy
b. food
c. oxygen.
d. carbon dioxide
Chapter 3 Cell Structure and Function
Chapter Preview Questions
3. Cells break down carbohydrates to get ____ for life processes.
a. energy
b. food
c. oxygen
d. carbon dioxide
Chapter 3 Cell Structure and Function
Chapter Preview Questions
4. Cells in green plants make
a. food and carbon dioxide.
b. water and carbon dioxide.
c. food and oxygen.
d. water and carbon dioxide.
Chapter 3 Cell Structure and Function
Chapter Preview Questions
4. Cells in green plants make
a. food and carbon dioxide.
b. water and carbon dioxide.
c. food and oxygen.
d. water and carbon dioxide.
Chapter 3 Cell Structure and Function
You hear that a pinch of soil may contain millions of organisms.
What optical tools would you use to see these organisms and to study their structure?
What is the structure of a cell?
Chapter 3 Cell Structure and Function
Prefix Meaning Example Word
chlor- green chloroplast A cellular structure that captures energy from sunlight
Prefixes
Chapter 3 Cell Structure and Function
Prefixes
Prefix Meaning Example Word
cyto- cell cytoskeletonThe framework inside a cell
Chapter 3 Cell Structure and Function
Prefix Meaning Example Word
multi- many multicellularHaving many cells
Prefixes
Chapter 3 Cell Structure and Function
Prefix Meaning Example Word
uni- one unicellularHaving one cell
Prefixes
Chapter 3 Cell Structure and Function
Apply It!
1. A chloroplast is a structure in plant cells. What color do you think achloroplast is?
green
2. What clue within the word cytoplasm lets you know that the word hassomething to do with cells?
the prefix cyto-
Chapter 3 Cell Structure and Function
Section 1: Discovering Cells
What are cells?How did the invention of the microscope contribute to knowledge about living things?What is the cell theory?How are the cells of multicellular organisms organized?
Chapter 3 Cell Structure and Function
Development of the Cell Theory
The cell theory states the following:• All living things are composed of cells.• Cells are the basic units of structure and function in living things.• All cells are produced from other cells.
Chapter 3 Cell Structure and Function
An Overview of CellsKey concept: Cells are the basic units of structure and
function in living things.Examples of function: obtaining oxygen, getting rid of waste,
obtaining food, growing, and more…Cells function similarly in all organisms, they carry out the
basic processes of life in similar ways.Cells are so small they are measured in micrometers
The invention of the microscopeMade it possible to discover and Learn about cells
Chapter 3 Cell Structure and Function
Unicellular and Multicellular
Unicellular, or single-celled, organisms include bacteria, the most numerous organisms on Earth. Multicellular organisms are composed of many cells.
Unicellular
Multicellular
Chapter 3 Cell Structure and Function
Multicellular Organisms
Categorized into:
1) Tissues
- Similar cells that work together for specific function
2) Organs
- Made of different tissues that work together
- Ie. Brain
3) Organ Systems
-A group of organs that work together to perform a major function
-Ie. Cells, tissues, and organs
Chapter 3 Cell Structure and Function
First Observations of Cells
1590ish invention of the microscopeKey concept: The invention of the
microscope made it possible for people to discover and learn about cells.
Robert Hooke•one of first people to observe cells•built his own microscope- one of the best of his time•observed cork which looked like small rectangular rooms they called cells
Chapter 3 Cell Structure and Function
First Observations of Cells
Anton van LeeuwenhookDutch businessman
Built simple microscopes in his spare time
Looked at drops of lake water, scrapings from teeth and gums, water from rain gutters
Animalcules- means “little animals,” small organisms that moved that he found in things like lake water
Chapter 3 Cell Structure and Function
Development of the Cell Theory
Schleiden- all plants are made of cellsSchwann- all animals are made of cellsVirchow- new cells are formed only from
cells that already exist
Chapter 3 Cell Structure and Function
Cell Theory
An explanation of the relationship between cells and living things
i. All living things are made of cells.
ii. Cells are the basic units of structure and function
iii. All cells are produced from other cells
Chapter 3 Cell Structure and Function
Unicellular and Multicellular
Unicellular- single celledMulticellular- many cellsKey concept: “In multicellular
organisms, cells are often organized into tissues, organs, and organ systems.
Tissue- a group of singular cells that work together
Organs- is made up of different kinds of tissue
Organ system- a group of organs wanted to what those
Chapter 3 Cell Structure and Function
Links on Cell Theory
Click the SciLinks button for links on the cell theory.
Chapter 3 Cell Structure and Function
What role do the cell wall and cell membrane play in the cell?What is the role of the nucleus in the cell?What organelles are found in the cytoplasm and what are their functions?How do cells differ?
Section 2: Looking Inside Cells
Chapter 3 Cell Structure and Function
Cell Wall
The cell wall is a rigid layer of nonliving material that surrounds the cells of plants & some other organisms.A plant’s cell wall helps to protect & support the cell.The cell wall is made of a strong, flexible material called cellulose, & many materials can pass through it.
Chapter 3 Cell Structure and Function
Plant and Animal Cells Activity
Click the Active Art button to open a browser window and access Active Art about plant and animal cells.
Chapter 3 Cell Structure and Function
Cell MembraneIn cells that do not have cell walls, the cell membrane is the outside boundary that separates the cell from its environment. (Barrier-like a window Screen)All cells have cell membranes.In cells with cell walls, the cell membrane is located just inside the cell wall. The cell membrane controls what substances come into & out of a cell. (ie. Food & oxygen)*In plant cells and animal cells
Chapter 3 Cell Structure and Function
Nucleus
The nucleus is the cell’s control center, directing all of the cell’s activities.
Chapter 3 Cell Structure and Function
Nuclear Envelope
The nucleus is surrounded by a protective membrane called the nuclear envelope.
Materials pass in & out of the nucleus through small openings, or pores, in the nuclear envelope.
Chapter 3 Cell Structure and Function
Chromatin
Directs the Nucleus
Strands that contain the genetic material, the instructions for directing the the cell’s functions.
Chapter 3 Cell Structure and Function
Cytoplasm
The cytoplasm is the region between the cell membrane & the nucleus.
Many cell organelles are found in the cytoplasm.
Chapter 3 Cell Structure and Function
Mitochondrion
Mitochondria are known as the “powerhouses” of the cell because they convert energy in food molecules to energy the cell can use to carry out its functions.
Chapter 3 Cell Structure and Function
Endoplasmic ReticulumThe endoplasmic reticulum is similar to the system of hallways in a building. Proteins and other materials move throughout the cell by way of the endoplasmic reticulum. The spots on this organelle are ribosomes, which produce proteins.
Chapter 3 Cell Structure and Function
Endoplasmic Reticulum
Passageways called the endoplasmic reticulum carry proteins & other materials from one part of the cell to another.
Chapter 3 Cell Structure and Function
Ribosomes
Small, grainlike bodies called ribosomes function as factories to produce proteins.
In plant and animal cells.
Chapter 3 Cell Structure and Function
Golgi BodyThe Golgi bodies receive proteins and other newly formed materials from the endoplasmic reticulum, package them, and distribute them to other parts of the cell.
Chapter 3 Cell Structure and Function
Chloroplasts
The Golgi Bodies release materials outside the cell.
In plants, & some other organisms, large, green structures called chloroplasts capture energy from sunlight & use it to produce food for the cell.
Chapter 3 Cell Structure and Function
Vacuoles
Large water-filled sacs called vacuoles are the storage areas of cells.
A vacuole stores food & other materials needed by the cell.
Chapter 3 Cell Structure and Function
Lysosomes
Small, round structures called lysosomes contain chemicals that break down certain materials in the cell.
Chapter 3 Cell Structure and Function
Organelles
Inside a cell are tiny structures called organelles, which carry out specific functions within the cell.The nucleus is a large, oval structure that acts as the “brain” of the cell.You can think of the nucleus as the cell’s control center, directing all of the cell’s activities.
Chapter 3 Cell Structure and Function
The Cytoplasm and Organelles
Click the Video button to watch a movie about cytoplasm and organelles.
Chapter 3 Cell Structure and Function
Bacterial Cells
Bacterial cells are smaller & different from plant & animal cells.
While a bacterial cell does have a cell wall & a cell membrane, it does not contain a nucleus.
The bacterial cell’s genetic material, which looks like thick, tangles string, is found in the cytoplasm.
Bacterial cells contain ribosomes, but none of the other organelles found in plant & animal cells
Chapter 3 Cell Structure and Function
Cell DiversityThe Variety is cell structure in cells reflects differences in cell
function.
A cells structure is complementary to it’s function
Example- Red blood cell shape to fit through tiny vessels
Chapter 3 Cell Structure and Function
What are elements and compounds?How is water important to the function of cells?What are the functions of carbohydrates, lipids, proteins, and nucleic acids?
Section 3: Chemical Compounds in Cells
Chapter 3 Cell Structure and Function
An element is a pure substance where all the atoms in a sample of matter have the same identity, and cannot be broken down into simpler substances. For example all of the elements in the periodic table.
Compounds are made from atoms of two or more elements that are combined chemically. Smallest unit of a compound is a molecule.
Chapter 3 Cell Structure and Function
Elements and CompoundsCarbon dioxide, which is found in gas bubbles, is a chemical compound. So is water.
Chapter 3 Cell Structure and Function
Most chemical reactions that take place within cells could not take place without water.
Many compounds in living things contain the element carbon, Compounds that do not contain carbon are called inorganic compounds. Water
and sodium chloride are familiar examples of inorganic compounds.
Has to have Carbon to be organic
Chapter 3 Cell Structure and Function
Compounds in Bacteria and Mammals
All cells contain carbohydrates, lipids, proteins, and nucleic acids, as well as water and other inorganic compounds. But do all cells contain the same percentages of these compounds? The graph compares the percentage of some compounds found in a bacterial cell and a cell from a mammal.
Chapter 3 Cell Structure and Function
Compounds in Bacteria and Mammals
Red bars represent percentages of compounds in bacterial cells; blue bars represent percentages of compounds in mammalian cells.
Reading Graphs:
What do the red bars represent? What do the blue bars represent?
Chapter 3 Cell Structure and Function
Compounds in Bacteria and Mammals
About 70%; the percentages are the same.
Interpreting Data:
What percentage of a mammalian cell is made up of water? How does this compare to the percentage of water in a bacterial cell?
Chapter 3 Cell Structure and Function
Compounds in Bacteria and Mammals
Proteins
Interpreting Data:
Which kind of compound–proteins or nucleic acids–makes up the larger percentage of a mammalian cell?
Chapter 3 Cell Structure and Function
Compounds in Bacteria and MammalsDrawing Conclusions:
In general, how do a bacterial cell and mammalian cell compare in their chemical composition?
They are similar, though mammalian cells have a lower percentage of nucleic acids, and bacterial cells have a lower percentage of lipids and fewer proteins.
Chapter 3 Cell Structure and Function
Carbohydrates, Lipids & Energy
Carbohydrate- energy-rich organic compound made up of carbon, hydrogen, and oxygen.
-Provide energy for the cell
- components for cell parts (cellulose-plants)
Lipids- energy-rich organic compounds made up of carbon, hydrogen, and oxygen
- Provide energy to the cells
- make up most of the cell membrane
Chapter 3 Cell Structure and Function
Proteins
Proteins- Large organic molecules made up of carbon, hydrogen, oxygen, nitrogen, and, in some cases, sulfur.
Foods- Meat, eggs, fish, nuts, beans
Made up of amino acids (20 but many due to combinations)
Enzyme- A type of protein that speeds up a chemical reaction in living things.
Chapter 3 Cell Structure and Function
Links on Proteins
Click the SciLinks button for links on proteins.
Chapter 3 Cell Structure and Function
Nucleic Acids
Very long organic molecules made up of carbon, oxygen, hydrogen, nitrogen, and phosphorus.
Contain the instructions that cells need to carry out all functions of life.
Types:
DNA- genetic material that carries info. About an organism and is passed from parent to offspring
- Found in chromatin in the nucleus
RNA- role in production of proteins
- Found in the cytoplasm as well as the nucleus
Chapter 3 Cell Structure and Function
How do most small molecules cross the cell membrane?Why is osmosis important to cells?What is the difference between passive and active transport?
Section 4: The Cell in Its Environment
Chapter 3 Cell Structure and Function
A Selective Barrier
The cell membrane protects the contents of the cell and helps control the materials that enter and leave.
Chapter 3 Cell Structure and Function
The Cell in its Environment
1. Selective Permeability – This means that some substances are allowed into a cell and others are not. Permeable means to “pass through”.
Chapter 3 Cell Structure and Function
Diffusion
In diffusion, molecules move from an area of higher concentration to an area of lower concentration.
Chapter 3 Cell Structure and Function
Ratios The concentration of a solution can be expressed as a ratio. A ratio compares two numbers. It tells you how much you have of one item in comparison to another. For example, suppose you dissolve 5 g of sugar in 1 L of water. You can express the concentration of the solution in ratio form as5 g:1 L, or 5 g/L.
Practice Problem
Suppose you dissolve 7 g of salt in 1 L of water. Express the concentration of the solution as a ratio.
7 g:1 L or 7 g/L
Chapter 3 Cell Structure and Function
Osmosis
In osmosis, water diffuses through a selectively permeable membrane. (Movement of water by diffusion)
Chapter 3 Cell Structure and Function
Passive and Active TransportPassive and active transport are two processes by which materials pass through the cell membrane. Active transport requires the cell to use its own energy, while passive transport does not.
Chapter 3 Cell Structure and Function
The Cell in its Environment
2. Two ways substances move in and out of cells – Passive and Active Transport
Chapter 3 Cell Structure and Function
The Cell in its Environment3. Passive Transport – Movement of material through a cell membrane
where energy is not required
a. Diffusion – the movement of molecules from an area of higher concentration to an area of lower concentration. Example: pond water organisms survive because oxygen in the pond water is at higher levels than inside the organism
Chapter 3 Cell Structure and Function
More on Cellular Transport
Click the PHSchool.com button for an activityabout cellular transport.