Biology I Chapter 7 Interest Grabber NOTEBOOK #1 Are All Cells Alike? — All living things are made up of cells. Some are composed of only one . Other organisms are made up of many cells. — 1. What are the advantages of a one- celled ? — 2. What are the advantages of an organism that is made up of many cells? Discovery of the Cell • There are several scientists that are responsible for understanding the cell. They are: 1. Robert Hooke - Observed a piece of cork and saw thousands of empty spaces. Coined the “cell” because they reminded him of the small rooms in the monastery. 2. Anton van Leeuwenhoek - first person to observe living cells. 3. Matthias Schleiden - All plants are made of cells. 4. Theodor Schwann - All animals are made of cells. 5. Rudolf Virchow - New cells come only from other cells. The Cell Theory

1. All living things are composed of cells. 2. Cells are the basic units of structure and function in living things. 3. New cells are produced from existing cells. Microscopes

• Compound light microscope - uses two lenses to focus on an image through which light passes through. • Transmission Electron Microscope (TEM) - sends a beam of electrons through a microscopic slice of a specimen. • Scanning Electron Microscope (SEM) - sends a beam of electrons over the surface of an object to produce a 3-D image. Prokaryotes

• They are cells that have genetic material that is not contained in a nucleus.

• Example - bacteria Eukaryotes

• Usually larger and more complicated than prokaryote cells. • Contain a nucleus in which their genetic material is separated from the rest of the cell. • Contain dozens of structures and internal membranes. Prokaryotic and Eukaryotic Cells

Cell membrane

Prokaryotic Cell

Cytoplasm Nucleus Eukaryotic Cell NOTEBOOK #2

1. What were the following scientists credited with: — Hooke, Leeuwenhoek, Schleiden, Schwann, Virchow

2. What are the three kinds of microscopes? 3. What is a prokaryote? 4. What is a eukaryote? NOTEBOOK #3 Interest Grabber Division of Labor — A cell is made up of many parts with different functions that work together. Similarly, the parts of a computer work together to carry out different functions.

— Working with a partner, answer the following questions.

— 1. What are some of the different parts of a computer? What are the functions of these computer parts?

— 2. How do the functions of these computer parts correspond to the functions of certain cell parts? Comparing the Cell to a Factory • The cell is made up of many tiny structures that act similar to specialized organs.

• The structures are known as organelles.

• Biologist split the eukaryotic cell into two parts: — Nucleus — Cytoplasm Nucleus

• The nucleus is compared to the main office of the factory.

• It is the control center.

• The nucleus contains nearly all the cell’s DNA and with it the coded instructions for making and other important molecules. Parts of the nucleus

• The nucleus is surrounded by a nuclear envelope.

• The envelope contains many different pores that allow materials such as proteins, RNA, and other molecules to travel to and from the rest of the cell.

• Just like the memos, instructions and blueprints move in and out of the office. Parts of the nucleus

• The nucleus contains granular material made up of DNA bound to proteins called chromatin. • During cell division, this chromatin condenses to form thread-like structures called chromosomes. • The nucleus also contains a small, dense region called the nucleolus which is responsible for the assembly of ribosomes. Ribosomes • One of the most important products of the cell is the making of proteins. • Proteins are assembled on ribosomes. • Ribosomes are small particles of RNA and found in two places throughout the cell: 1. Endoplasmic Reticulum 2. Cytoplasm • In the factory, they are the machines that produce the product. Endoplasmic Reticulum • The endoplasmic reticulum is the site where lipid components of the cell membrane are assembled, along with proteins and other materials that are exported from the cell.

• There are two types of ER’s: 1. Rough ER 2. Smooth ER • Rough ER • Rough ER is responsible for producing proteins that are exported from the cell.

• It is called rough because there are ribosomes found on the surface of the ER which gives it a bumpy surface.

• The proteins made by these ribosomes enter the ER where they are modified. • Smooth ER

• Ribosomes are not found on its surface. • Contains enzymes that perform specialized tasks such as the synthesis of membrane lipids and the detoxification of drugs. • Liver cells have large amounts of smooth ER. NOTEBOOK #4 1. What is the nucleus? 2. What is it surrounded by?

3. What is found in the nucleus?

4. What is the job of the ribosomes?

5. Where are the ribosomes found?

6. What is the job of the ER? 7. What are the two kinds of ER and explain the difference.

• Proteins that are made in Golgi Apparatus the rough ER move into the golgi apparatus.

• They are a stack of apposed membranes.

• The function of the golgi apparatus is to modify, sort, and package proteins and other materials from the ER for storage in the cell or secretion outside the cell.

• Golgi is the customization shop where the finishing touches are put on the product. Lysosomes

• They are small organelles filled with enzymes.

• They have two major jobs:

1. Digest or breakdown lipids, carbohydrates, and proteins into small molecules that can be used by the cell.

2. Ingest and destroy old and worn-out organelles.

• The lysosome can be compared to the cleanup crew of the factory.

• Vacuoles are the storage area of the cell. They store things such as , salts, proteins, and carbohydrates.

• In plants, there is usually a large central that is filled with liquid. The pressure built up in the vacuole make it possible to support heavy structures.

• In single-cell organisms, such as the , they contain a contractile vacuole that pumps out excess water to help maintain homeostasis.

• Homeostasis is the maintenance of a controlled internal environment. NOTEBOOK #5

1. What is the gologi apparatus?

2. What is the job of the golgi apparatus?

3. What are lysosomes?

4. What is the job of the lysosome?

5. What is a vacuole?

6. What is the job of the vacuole?

7. What process is maintained by the vacuole? Mitochondria • Mitochondria are organelles that convert the chemical stored in food into compounds that are more convenient for the cell to use. • Mitochondria have two membranes - an outer membrane and an inner membrane that is folded up to create more surface area.

• Mitochondria are inherited from the cytoplasm of the ovum, or egg. • Called the “Powerhouse” of the cell.

• ATP is made here. Chloroplasts

• Chloroplasts are organelles that capture the energy from sunlight and convert it into chemical energy in a process called photosynthesis.

• They act as solar panels. The chemical that absorbs the sunlight is a green pigment called chlorophyll. DNA

• Mitochondria and Chloroplasts contain their own genetic information in the form of small DNA molecules.

• They are believed to be descendants of ancient prokaryotes.

• The idea suggests that the ancient prokaryotes developed a symbiotic relationship with the eukaryotes and actually took up residence within the eukaryotic cell.

• This idea is called the endosymbiotic theory. Cytoskeleton • The cytoskeleton is a network of protein filaments that helps the cell to maintain its shape. The cytoskeleton is also involved in movement.

• The two main types of protein filaments — Microfilaments - thread-like structures made of . — Microtubules - hollow structures made of tubulins. — Play an important role in cell division. — Make up centrioles, cilia, and flagella. NOTEBOOK #6

1. What is the job of the mitochondria?

2. What is made there?

3. How is mitochondria inherited?

4. What is the job of the choloroplast?

5. What is the chemical that absorbs the solar energy?

6. According to the endosymbiotic theory, how did mitochondira and chloroplasts end up living inside of cells?

7. What is the cytoskeleton and what is its job? Venn Diagrams Prokaryotes Eukaryotes Nucleus NOTEBOOK #7 Endoplasmic reticulum Golgi apparatus Cell membrane Lysosomes Contain DNA Vacuoles Mitochondria Cytoskeleton

Animal Cells Plant Cells

Cell membrane Ribosomes Nucleus Endoplasmic reticulum Centrioles Golgi apparatus Chloroplasts Lysosomes Vacuoles Mitochondria Cytoskeleton Figure 7-5 Plant and Animal Cells

Plant Cell Smooth endoplasmic Vacuole reticulum Ribosome (free) Chloroplast Ribosome (attached) Cell Membrane Nuclear Cell wall envelope

Nucleolus

Golgi apparatus Nucleus

Mitochondrion Rough endoplasmic reticulum Figure 7-5 Plant and Animal Cells

Animal Cell

Ribosome (attached) Ribosome Nucleolus (free) Nucleus Cell Membrane Nuclear envelope Mitochondrion

Rough Smooth endoplasmic endoplasmic reticulum reticulum

Golgi apparatus Centrioles Figure 7-11 Cytoskeleton

Cell membrane

Endoplasmic reticulum

Microtubule

Microfilament

Ribosomes Mitochondrion NOTEBOOK #8 Interest Grabber In or Out? — How is a window screen similar to a cell membrane? Read on to find out.

— 1. What are some things that can pass through a window screen?

— 2. What are some things that cannot pass through a window screen? Why is it important to keep these things from moving through the screen?

— 3. The cell is surrounded by a cell membrane, which regulates what enters and leaves the cell. Why is it important to regulate what moves into and out of a cell? Facilitated Diffusion Glucose molecules

High Concentration

Cell Membrane

Protein Low channel Concentration Figure 7-12 The Structure of the Cell Membrane

Outside of cell

Carbohydrate chains Proteins Cell membrane

Inside of cell Protein (cytoplasm) channel Lipid bilayer Figure 7-15 Figure 7-19

Molecule to be carried

Energy

Molecule being carried NOTEBOOK #9

1. What part of the cell membrane aids in facilitated diffusion?

2. What is the structure of the cell membrane?

3. What is osmosis?

4. What is active transport? Interest Grabber From Simple to More Complex

— Many multicellular organisms have structures called organs that have a specific function and work with other organs. — Working together, these organs carry out the life processes of the entire organism. Interest Grabber continued NOTEBOOK #10

— 1. Some activities cannot be performed by only one person, but need a team of people. What type of activity requires a team of people to work together in order to complete a task?

— 2. What do you think are some characteristics of a successful team?

— 3. How is a similar to a successful team? Levels of Organization

Muscle cell Smooth muscle Stomach Digestive system Interest Grabber NOTEBOOK #11 An Important Process — While walking along a dusty path, you begin to cough. As you continue your walk, a small insect comes flying toward you. You blink and then duck so that it misses you. These actions are just a few examples of homeostasis. Homeostasis is the process by which organisms keep internal conditions relatively constant despite changes in their external environments. 1. List three other examples of homeostasis that occur in organisms. 2. Why is homeostasis important to an organism? Homeostasis The process by which organisms keep internal conditions relatively constant despite changes in external environment. Thermoregulation the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different.

Water Regulation () the active regulation of the osmotic pressure of an organism's fluids to maintain the homeostasis of the organism's water content; that is it keeps the organism's fluids from becoming too diluted or too concentrated Oxygen Regulation The physiological regulation of oxygen in plants and animals NOTEBOOK #12

1. What is Thermoregulation? 2. What is Water Regulation? 3. What is Oxygen Regulation?