Cell TheoryCell Theory

Anton van LeeuwenhoekAnton van Leeuwenhoek 1674 Holland (isn’t 1674 Holland (isn’t

that weird…) that weird…) FirstFirst compound light compound light

microscopemicroscope First to see bacteria, First to see bacteria,

called them called them “animacules”“animacules”

Studied pond water, Studied pond water, blood, tooth scrapingsblood, tooth scrapings

Robert HookeRobert Hooke 1655 England1655 England Coined the term Coined the term

““cellcell” to describe ” to describe the chambers in the chambers in corkcork

Cell walls look like Cell walls look like little rooms in the little rooms in the monastery monastery

Matthias SchliedenMatthias Schlieden 1837 Germany1837 Germany All All plantsplants are made are made

of cellsof cells

Theodor SchwannTheodor Schwann 1837 Germany1837 Germany All All animalsanimals are made are made

of cellsof cells Once, while talking at Once, while talking at

dinner with his friend, dinner with his friend, Matthias Schleiden, Matthias Schleiden, Schwann compared Schwann compared the parts of plants the parts of plants and animal cells, and and animal cells, and they realized that they they realized that they had similar parts!had similar parts!

Rudolf VirchowRudolf Virchow 1837 Germany1837 Germany First to see leukemia First to see leukemia

cellscells Has an autopsy Has an autopsy

method named after method named after himhim

Cells can Cells can onlyonly arise arise from from

pre-existing cellspre-existing cells

Francesco RediFrancesco Redi 1668 Italy1668 Italy Disproved the Disproved the

theory of theory of spontaneous spontaneous generationgeneration

Francesco Redi’s ExperimentFrancesco Redi’s Experiment

Louis PasteurLouis Pasteur 1862 France1862 France Disproved the theory Disproved the theory

of spontaneous of spontaneous generationgeneration

Developed the Developed the process of process of pasteurizationpasteurization

Pasteur’s Experiment

From the work of these From the work of these and many other and many other

scientists, we have the scientists, we have the Cell TheoryCell Theory

Cell TheoryCell Theory1.1. All living things are made up of All living things are made up of

at least one cellat least one cell..2.2. The cell is the basic unit of The cell is the basic unit of

structure and function in living structure and function in living thingsthings..

3.3. Cells come only from other Cells come only from other living cellsliving cells..

How did the microscope change How did the microscope change human understanding of life? human understanding of life?

Why were cells not discovered before the Why were cells not discovered before the microscope was invented?microscope was invented?

Many diseases, such as strep throat, are Many diseases, such as strep throat, are caused by microscopic organisms. Why might caused by microscopic organisms. Why might a microscope be an important tool for a doctor? a microscope be an important tool for a doctor?

Who’s work was the most important in the Who’s work was the most important in the formation of the cell theory? Justify your formation of the cell theory? Justify your answer with details from your notes and/or answer with details from your notes and/or video. video.

Levels of Organization in Levels of Organization in Multicellular OrganismsMulticellular Organisms

Organelles Organelles Cells Cells Tissues Tissues Organs Organs Organ Systems Organ Systems Organism* Organism*

* An * An

organism organism

can be can be

unicellularunicellular

Grade 8 Review Grade 8 Review On loose leaf to hand in for a On loose leaf to hand in for a

classwork grade tomorrowclasswork grade tomorrowTest Test TOMORROW:TOMORROW:

In the Earth’s Surface Book:In the Earth’s Surface Book: Complete questions

• 12-16 on pg 105• 18, 20 and 22 on pg 105• 23-25 on pg 106• 1-8 on pg 107• 5, 6, 10, 15 and 16 on pg 139• 20 on pg 173

If students finish early:If students finish early:Start reading section 4.2 and take 2 column Start reading section 4.2 and take 2 column

notes. Fold notebook page in half:notes. Fold notebook page in half: SoilSoil

Four materials Four materials that make up that make up soilsoil

Organic Organic materialmaterial

Mixture of weathered rock Mixture of weathered rock particles and other materialsparticles and other materials

Weathered rock, organic Weathered rock, organic material, water and airmaterial, water and air

Remains and waste products of Remains and waste products of plants and animals as well as plants and animals as well as HUMUS (decaying material)HUMUS (decaying material)

Kind of soil depends Kind of soil depends on many factorson many factors

Soil horizons (A, B and Soil horizons (A, B and C)C)

Kind of rock, climate, Kind of rock, climate, landforms, plant cover, landforms, plant cover, animals and other animals and other organismsorganisms

A – upper layer A – upper layer (topsoil) most organic (topsoil) most organic material, often dark material, often dark colored because of all colored because of all the humusthe humus

B – little organic B – little organic material, brownish-material, brownish-reddish, clay and reddish, clay and mineralsminerals

Soil horizons (A, B and Soil horizons (A, B and C)C)

Soil propertiesSoil properties

C – deepest layer, C – deepest layer, largest and least largest and least weathered rock weathered rock particles, light particles, light yellowish-brown in coloryellowish-brown in color

Texture, color, pore Texture, color, pore space, chemistryspace, chemistry