The Microscope, Cells Structure, Processes, & Reproduction 7 th Grade Life Science Dutchtown Middle School.

The Microscope,Cells Structure, Processes, &

Reproduction

7th Grade Life ScienceDutchtown Middle School

S7L2 Students will describe the structure and function of cells, tissues, and organ system.

a. Explain that cells take in nutrients in order to grow and divide and to make need materials.

b. Relate cell structures (cell membrane, nucleus, cytoplasm, chloroplasts, mitochondria) to basic cell functions.

The Microscope

The Microscope

http://www.youtube.com/watch?v=Ue-86MDmjnsMicroscope: The Tube that Changed the World

• Between 1590 and 1600 several scientist had their hand in creating what we know call the microscope.

• They found that by putting curved pieces of glass – called lenses – in a tube, they could make a microscope.

• Early microscopes-lenses made images larger, but not always clear.

The Microscope

1. Modern microscopes that use lenses to bend light.a. A simple microscope has one lens while a

compound microscope has two sets of lenses.b. A stereomicroscope has two eyepieces,

and creates a three-dimensional image.c. Powers of the eyepiece multiplied by objective lenses determine total magnification.

The Microscope

2. Electron microscopes are more powerful than other microscopes.

a. Use a magnetic field in a vacuum to ben electronic beams.b. Images must be photographed or produced electronically.

Question

What are some differences between electron microscopes and other microscopes?

• Lenses or magnetic fields

• Viewing of the image• Magnification

Robert Hooke

The Wacky History of Cell Theory http://www.youtube.com/watch?v=4OpBylwH9DU

• In 1665, Robert Hooke, used a microscope to look at thin slices of a plant material called cork.

• Robert Hooke identified tiny box-like structures. He named these structures cells.

• Over the years, scientist used microscopes to observe countless living and nonliving materials.

• They discovered that all living things are made of cells, while non-living things are not.

Development of Cell Theory

The cell theory resulted from many scientist observations and conclusions.

Cell Theory1. The basic unit of organization is the cell.2. All organisms are composed of one or more

cells.3. New cells come from old cell through cell

division.

Cell Structure

Cell Structures Vocabulary

MitochondriaOrganelleCell WallCell MembraneCytoplasmChloroplastEndoplasmic ReticulumVacuoleProkaryoteEukaryoteNucleusOrganization of LifeCellTissueOrganOrgan SystemOrganism

Cell Structure

1. Cells are the smallest units of living things.2. Cells are known as the tiny building blocks of life.3. Common cell structures – outer covering called cell membrane and internal gelatin like cytoplasm

a. Comparing cells – size and shape relate to function.

Cell Structure

4. There are two types of cells:a. Prokaryotic cells lack membrane-bound internal

structures.b. Eukaryotic cells contain membrane-bound internal

structures.

Prokaryotic & Eukaryotic Cellhttp://www.usatestprep.com/movies/119/519/3258/159?key=UTXM7QH36DQ

All CellsMembrane

Genetic MaterialCytoplasm (viscous – thick)

Prokaryotic

• Primitive & Small• Lack Organelles/No Nucleus• Ribosomes• May have Chlorophyll• Genetic Material• Eubacteria/Archeabacteria• Autotrophs

Eukaryotic

• True Cell• All Organelles – Nucleus• Organized• More Complex• Genetic Material DNA/RNA

found in the Nucleus• Chlorophyll found in Chloroplast• Autotrophs and Heterotrophs

Cell Organization

Cell Wall

Composed of cellulose, a cell wall grows, gives shape to, and protects the cells of plants, algae, fungi, and most bacteria.

Cell Organization

Cell Membrane

The protective layer around all cells.a. For cells with cell walls, the cell

membrane is inside the cell wall.b. A cell membrane allows food and oxygen

into the cell and waste products out of the cell.

Cell Organization

CytoplasmGelatin like substance inside the cell membrane.1. Cytoskeleton is the scaffolding like structure

in cytoplasm which helps cell keep its shape.2. In the cytoplasm, eukaryotic cells have

organelles which help with cell life processes.

Cell Organization

Nucleus The nucleus contains instructions for everything the cell does.

DNA is also found within the nucleus.

Cell Organization

Energy-processing Organelles

Energy-processing organelles help cells do their work.a. Green organelles in plant cells contain

chloroplasts to make food.b. Organelles which release energy from food

are called mitochondria.

Cell Organization

Manufacturing Organelles

a. Ribosomes make proteins for cell activities.b. Some ribosomes attach to the rough

endoplasmic reticulum, which is a series of smooth or rough membranes that move material around in a cell.

Cell Organization

Transporting and Storing Organelles

a. Golgi bodies move substances out of a cell or to other parts of a cell.

b. Vacuoles – membrane bound temporary storage spaces of water, nutrients, & waste.

Cell Organization

Recycling Organelles

Lysosomes break down food molecules and cell waste.

Review of Cell Organelles

• Cell Wall – gives added support and protection• Cell Membrane – surrounds the cytoplasm and

protects the cell.• Cytoplasm – jelly-like substance that fills the cell.• Nucleus – Controls activities of the cell.• Chloroplasts – produce food• Mitochondria – provide energy• Vacuole – stores water, food, and wastes• Lysosomes – break down food molecules & cell waste

Review of Cell Organelles

• Ribosome – protein is made on this organelle• Golgi bodies – sort protein and other cellular

substances and deliver to vesicles.• Endoplasmic Reticulum (ER) – a series of

folded membranes in which materials can be processed and moved around inside of the cell.

Plant Cell

Plant Cell Organelles• Cell Wall• Cell Membrane• Cytoplasm• Nucleus/Nucleolus• Chloroplasts• Mitochondria• Vacuole• Endoplasmic Reticulum (ER)• Ribosome• Golgi bodies

Animal Cell

Organelles• Cell Membrane• Cytoplasm• Cytoskeleton• Nucleus/Nucleolus• Mitochondria• Ribosome• Lysosome• Vacuole• Endoplasmic reticulum• Golgi bodies

Cells & Their Functions

Every cell carries out basic life jobs or functions.• All cells use energy.• All cells get rid of wastes.• All cells can reproduce. They do this by dividing.• Most living things are tiny organisms made of

one cell. (Unicellular)• Larger organisms, plants & animals, are made of

many cells.

From Cell to Organism

1. Tissue – group of similar cells working together on one job.

2. Different types of tissues working together make up an organ.

3. A group of organs working together on a particular function form an organ system.

Cells are the building blocks of life…

• In a multi-celled organism, different cells do different jobs.– A group of similar cells working together to do a

job make up TISSUE.– A group of different tissues working together are

an ORGAN.– A group of organs working together make up an

organ system.

Levels of Cellular Organization

Organ System

Circulatory System

OrganHeart

TissueHeart Tissue

CellHeart Cell

Level of Cell Organization

Question

What are some functions of cell parts?

• Protection• Providing shape• Processing energy• Making, transporting,

and storing substances

Big Ideas

• Cells take in nutrients to grow and divide and make needed materials.

• Cell structure is related to cell function• Cells are interdependent.• The levels of cellular organization:

Cells Tissue organs systems organism

Cell Processes

S7L2 Students will describe the structure and function of cells, tissues, and organ system

a. Explain that cells are organized into tissues, tissues into organs, organs into systems, and systems into organisms.

b. Explain that tissues, organs, and organ systems serve the needs cells have for oxygen, food, and waste removal.

c. Explain the purpose of the major organ systems in the human body (i.e. digestion, respiration, reproduction, circulation, excretion, movement, control, and coordination, and for protection from disease.)

Matter & Energy

• Everything around you is made up of matter and energy.

• Matter is anything that has mass and takes up space.

• Energy can hold matter together or break it apart.

Organic Compounds

Organic compounds contain carbon and hydrogen and are usually associated with living things or things that once were alive.

Organic Compounds

Four groups of organic compounds make up all living things:1. Carbohydrates - supply energy for cell processes2. Lipids - store and release large amounts of energy.3. Proteins – are the building blocks of many structures.

1. Amino Acids – make up protiens2. Enzymes – regulate nearly all chemical reactions in cells

4. Nucleic Acids- store important coded information in cell

Inorganic Compounds

Usually made from elements other than carbon.

Water is an inorganic compound.

Inorganic Compounds

The Importance of Water

1. Living things are composed of more than 50 percent water and depend on it to survive.

2. All chemical reactions in living things take place in water solutions.

3. Most living things use water to transport materials through their bodies.

Cell CompositionCell’s Composition Cells are 90% water (Inorganic Compound). Water makes up most of blood; most chemical reactions occur in water.The rest of the present molecules are: (Organic Compounds Found in Living Things)• 50% protein • 15% carbohydrate • 15% nucleic acid • 10% lipid • 10% others

Elements That Make Up the Human Body By elements, a cell’s composition by mass is: • 10% Hydrogen • 63% Oxygen • 20% Carbon • 3% Nitrogen • 4% Other trace elements such as iron, calcium, etc.

Question

What are you made of? Organic compounds, including carbohydrates, lipids, proteins, and nucleic acids. Inorganic compounds like water.

Essential Questions• How do you explain the relationship between the structures and

functions of cell organelles?• Why is each part of the cell essential to survival?• How is a living organism the sum of all of its parts?• Why must cells absorb energy and nutrients?• How do cells, tissues, organs, and organ systems relate to the

complexity of living organisms?• How does scientific development rely on our knowledge of cells?• What happens when cells cease to function adequately or at all?• Can plant and animal cells function without sunlight? Explain.• What do cells tell us about basic processes of life…life, death, and

reproduction?• How are cells like building blocks?

Moving Cellular Materials

Cell Processes Vocabulary

OsmosisDiffusionActive TransportPassive TransportEquilibriumEndocytosisExocytosisMetabolismPhotosynthesisCellular Respiration

Moving Cellular Materials

Cells have a selectively permeable membrane that regulates what goes into or out of the cell.

Cell Membrane

• The permeable membrane allows the molecules to pass through. An impermeable membrane doesn’t allow anything to pass. Only some molecules can pass through a semi-permeable membrane – usually only small molecules pass through quickly.

Passive TransportPassive transport is the movement of substances through the cell membrane without the input of energy.

There are 3 types of passive transport: diffusion, osmosis, and facilitated diffusion.

1. Diffusion is the random movement of molecules from areas where there is a high concentration to areas where there a low concentration. (Example: Scent of perfume, food color lab) Likewise, equilibrium occurs when the molecules of are spread evenly throughout another substance. (Example: Carrot sticks lab, carrots are crisp)

2. Osmosis is the diffusion of water through a cell membrane. (Example: gummy bear lab)

3. Facilitated diffusion, transport proteins move substances into and out of the cell.

Active Transport

Cells use/require energy to move molecules by active transport

Cells move large or bulky particles through cell membranes by endocytosis and exocytosis.

Endocytosis is the process in which a substance is taken into a cell by surrounding it with the cell membrane, forming a sphere called a vesicle.

Exocytosis is the process in which the membrane of the vesicle fuses with the cell membrane and the vesicle’s contents are released outside the cell.

Question

What needs to be transported through your cells’ membranes?

Transported in the cell:• Nutrients from food• Oxygen• Water

Transported out of the cell:• Wastes• Carbon dioxide

Essential Questions

• How do cells, tissues, organs, and organ systems relate to one another?

• How the functions of organ systems interact?• How do tissues, organs, and organ systems serve cells needs

for oxygen, food, and waste removal?• How do the higher levels of organization serve the needs of

cells?• How do the systems compare in different organisms?• How does the hierarch of organisms result in the complexity

and diversity of organisms?• How does reproduction vary among organisms?

How do living things get energy?

Metabolism

Metabolism is the total of all chemical reactions in an organism.

The chemical reactions of metabolism require enzymes.

Cells use chemical reactions to change the chemical energy stored in food into forms need to perform activities.

How do living things get energy?

Photosynthesis

Photosynthesis is the process that plants and other organisms use to convert light energy into chemical energy or sugars to be used as food.

Producers are organisms that make their own food.Consumers are organisms that can’t make their own food.

Chlorophyll and other pigments are used in photosynthesis to capture light energy which is used to produce sugar and oxygen.

How do living things get energy?

Cellular Respiration

Cellular respiration is the process in which chemical reactions break down food molecules into simpler substances and release stored energy.

How do living things get energy?

Cellular Respiration

Cellular respiration of carbohydrates begins in the cytoplasm.a. Carbohydrates are broken down into glucose

molecules.b. Each glucose molecule is broken down into

two simpler molecules releasing energy.

How do living things get energy?

Cellular Respiration

Cellular respiration moves into the mitochondria.a. The two simpler molecules are broken down

again, releasing much more energy.b. This process uses oxygen and produces

carbon dioxide and water as wastes.

How do living things get energy?

Fermentation

Cells that do not have enough oxygen for cellular respiration use this process t release some of the stored energy in glucose molecules.

1. Entire process occurs in the cytoplasm.2. Produces lactic acid, alchol, and carbon dioxide

waste.

Almost opposite of each other…

Photosynthesis

Produces sugars and oxygen, which are used in cellular respiration.

Cellular Respiration

Produces carbon dioxide and water which are used in photosynthesis.

Question

You are about to go for a run. What does your body need to make the energy you will use?

• Water to transport nutrients to the cells.

• Carbohydrates or lipids as a source of chemical energy.

• Enzymes to assist the chemical reactions.

• Oxygen to fuel respiration.

Cell Reproduction

S7L2 Students will describe the structure and function of cells, tissues, and organ system.

VocabularyCell ReproductionMitosisMeiosis Sexual ReproductionAsexual ReproductionHaploidDiploidCycleChromosomeFertilizationEggSperm

Cell Division and Mitosis