GOAL SETTING: 1. Unit 2 Test grade = ____% 2. I prepared by… 3. Next time I will prepare by… 4. Goal for next time = ____ If you met your goal + got an A: You may maintain or improve. If you met your goal but did not get an A: You must improve at least 1 percentage points. If you did not meet your goal it stays the same. 11-1

1. What is inside a cell (anything that comes to mind - you don't have to be correct at this point)?

What is made of cells (living cells)? Everything? …NO, so what?

What is a cell (define cell in your own words)?

Use a Whale Book (by yourself): 1. Define cell, eukaryote, + prokaryote 2. What are the 3 main ideas of cell theory (page 191)? 3. Answer # 1 on page 195 (use your brain – what do you think?) 4. READ Two Basic Cell Types (pages ) and afterwards answer # 4 on page 195 This is due before the end of the period! If finished early, remain silent.

Use a Whale Book (by yourself): 1. Define unicellular, multicellular, organelle, plasma membrane, cell wall, cytoplasm 2. What lipid are cell membranes made of (from last chapter – jigsaw notes)? 3. What were the 7 characteristics of life (from Unit # 1 Notes)? 4. READ Energy Transformer (pages 201 and 204) and answer # 4 on page 210. This is due before the end of the period! If finished early, remain silent.

11-3 Describe and interpret relationships between structure and function at various levels of biological organization. TODAY: What is cell theory?

The Discovery of the Cell What is a cell? Cell = smallest unit that can carry out all the processes of life

The Discovery of the Cell Cell = smallest unit that can carry out all the processes of life Life is ORGANIZED Life responds to STIMULI (responsiveness) Living things maintain HOMEOSTASIS Living things have a METABOLISM Living things GROW and DEVELOP Living things REPRODUCE Living things EVOLVE

The Discovery of the Cell What is the cell theory? The cell theory states: - All living things are made up of cells. - Cells are the basic units of structure and function in living things. - New cells are produced from existing cells.

Development of Cell Theory Mid-1600s scientists began to use microscopes to observe living things. In 1665, Englishman Robert Hooke used an early compound microscope to look at a nonliving thin slice of cork, a plant material. Under the microscope, cork seemed to be made of thousands of tiny, empty chambers that Hooke called “cells”. The term cell is used in biology to this day.

In Holland, Anton van Leeuwenhoek examined pond water and other things, including a sample taken from a human mouth. He drew the organisms he saw in the mouth—which today we call bacteria. Development of Cell Theory

Soon after Leeuwenhoek, observations made by other scientists made it clear that cells were the basic units of life. In 1838, German botanist Matthias Schleiden concluded that all plants are made of cells. The next year, German biologist Theodor Schwann stated that all animals were made of cells. Development of Cell Theory

In 1855, German physician Rudolf Virchow concluded that new cells could be produced only from the division of existing cells, confirming a suggestion made by German Lorenz Oken 50 years earlier. Development of Cell Theory

These discoveries are summarized in the cell theory, a fundamental concept of biology. The cell theory states: 1. All living things are made up of cells. 2. Cells are the basic units of structure and function in living things. 3. New cells are produced from existing cells. Development of Cell Theory

REVIEW

Cell Diversity Cell Shape Cell Shape –Shape reflects function Function of Nerve cell? Shape? Function of Skin Cells? Shape?

Cell Diversity Cell Size Cell Size –Cells vary in size  Nerve cells in giraffe neck vs. Human egg cell - size of a. –Cell size is limited by it’s surface area to volume ratio

What is the problem with increasing cell size? What is the problem with increasing cell size? Volume increases faster than surface area as a cell grows Volume increases faster than surface area as a cell grows –PROBLEM:  needed materials can’t get in fast enough (O2, glucose) and wastes out fast enough (CO2)  Notice SA increased only 25 times and the volume increase 125 times

Prokaryotic vs. Eukaryotic Cells – –Eukaryotes are cells that enclose their DNA in nuclei. – –Prokaryotes are cells that do not enclose DNA in nuclei.

Cell Types Prokaryote Prokaryote –No nucleus –No membrane bound organelles –Still have DNA mass in center of cell –Small / simpler than eukaryotic cells –Example:  Bacteria

Cell Types Eukaryote Eukaryote –1 or more cells –Have membrane bound organelles –Larger / more complex than prokaryotes –Examples:   plants, animals, fungi, and organisms commonly called “protists.”