1. Ch. 7 Cell Structure & Function
Unit 3 Cells
Ch. 7 Cell Structure & Function

2. The Discovery of the Cell
Robert Hooke used compound light microscope to view cork, a plant material
Cork had 1000’s of chambers in it - named the chambers “cells”

3. The Cell Theory Cells - the basic unit of life
Developed the cell theory:
All living things are made of cells
Cells are the basic units of structure & function in living things
New cells are produced from preexisting cells

4. Exploring the Cell

5. Prokaryotes & Eukaryotes
Cells are in 2 broad categories depending on whether they have a nucleus
Nucleus - a membrane-enclosed structure that contains the cell’s DNA
Controls the cells activities

6. Prokaryotes & Eukaryotes
Eukaryotes - cells that have a nucleus
Prokaryotes - cells that do not have a nucleus

7. Comparing the Cell to a Factory
Organelles - “little organs”, structures within a cell
Cytoplasm - portion of the cell outside the nucleus

8. Nucleus
Nucleus - contains cell’s DNA, & with it, the instructions for making proteins
Nuclear envelope - membrane that surrounds the nucleus
Nucleolus - center of nucleus, where ribosomes are formed

9. Ribosomes Proteins are made on ribosomes
Ribosomes - small particles of RNA & protein found throughout the cytoplasm
Site of protein synthesis (to make)

10. Endoplasmic Reticulum
Endoplasmic reticulum - ER - site where proteins are assembled

11. Golgi Apparatus
Golgi apparatus - function is to package proteins from the ER
The “packaging center” of the cell

12. Lysosomes Lysosomes - small organelles filled with enzymes
They break down (digest) lipids, carbohydrates, & proteins into molecules that can be used by the cell

13. Vacuoles
Vacuoles - saclike structures that store materials like water, salts, proteins, & carbs.

14. Mitochondria & Chloroplasts
Mitochondria - organelles that convert chemical energy stored in food to compounds that can be used by the cell
The “powerhouse” of the cell

15. Mitochondria & Chloroplasts
Chloroplasts - organelles that capture energy from sun & convert it into chemical energy, during photosynthesis
Green structures, only found in PLANT cells

16. Cytoskeleton
Cytoskeleton - a network of protein filaments that help the cell maintain its shape

17. Cell Membrane
Cell membrane - regulates what enters & leaves the cell, also provide protection & support
Contains lipid bilayer - 2 layers of lipids

18. Cell Boundaries
Cell wall - found in plant cells, fungi, algae, & many prokaryotes (NOT in animal cells)
Provides support & protection for the cell

20. Diffusion Through Cell Boundaries
Every living cell exists in a liquid environment that it needs to survive
Cells have a different concentration or amount of substances within them

21. Diffusion Through Cell Boundaries
Diffusion - movement of molecules from an area of greater concentration to lesser concentration to create equilibrium
Does NOT require energy
Equilibrium - when the concentration of a substance is the same on both sides of a membrane

23. Osmosis
Osmosis - diffusion of water through a selectively permeable membrane, until equilibrium is reached

24. The Effects of Osmosis on Cells

25. Facilitated Diffusion
Facilitated diffusion - molecules that can’t diffuse across the cell’s lipid bilayer on their own, move through protein channels instead

26. Active Transport
Active transport - requires energy moves against the concentration gradient from low to high

27. Unicellular Organisms
Cells are the basic units of all organisms, but sometimes a cell is the organism
A single-celled organism is also called a unicellular organism

28. Multicellular Organisms
Organisms made up of many cells are multicellular
Cell specialization - cells throughout an organism can develop in different ways to perform different tasks

29. Cell Specialization

30. Levels of Organization
The levels of organization in a multicellular organism are individual cells, tissues, organs, & organ systems

31. Levels of Organization
Tissue - a group of similar cells that perform a particular function
Organ - many groups of tissue working together
Organ system - a group of organs working together to perform a specific function