Unit 5 Cells and Life Biology

I. Levels of Organization a. Elements and Atoms i. Atoms are the smallest building blocks of our world ii. An element is a substance made up of the same atom

I. Levels of Organization b. Compounds and Molecules i. A compound is when multiple different atoms combine with each other ii. The smallest part of a compound is called a molecule 1. Example: Carbon Dioxide is a molecule made of two different atoms, one carbon and two oxygens

I. Levels of Organization iii. Some of the main compounds in living things are Carbohydrates, Lipids, Proteins, and Nucleic Acids 1. Carbohydrates: provide cells energy 2. Lipids: form structures in the cell and they store energy 3. Proteins: form body structures 4. Nucleic Acids: are used to make DNA a. DNA is what carries our genetic material

I. Levels of Organization c. Cells i. A cell is the basic unit of structure and function of living things ii. If a living thing has only one cell it is called a unicellular organism iii. If a living thing has more than one cell it is called a multicellular organism 1. Plants and Animals are multicellular organisms 2. A multicellular organism has many different looking cells

Warm Up #6 1. Name the first four different levels of organizations in living things. 2. Name and Describe two of the four compounds.

I. Levels of Organization

d. Tissues, Organs and Organ Systems i. Tissues: a group of similar cells that work together to perform a certain function 1. Example: The brain is made up of mostly nerve tissue, which consists of nerve cells. These nerve cells relay information to the rest of the body 2. Give another example of a system

I. Levels of Organization ii. Organ: is made of different kinds of tissues that function together 1. Example: the brain has blood vessels that give oxygen to the brain cells so that they will function correctly 2. What is an example of another organ?

I. Levels of Organization iii. Organ System: Two or more organs working together to perform a given function 1. Example: your respiratory system and your circulatory system. Your respiratory system brings in the oxygen your body needs and the circulatory system take the oxygen to the different parts of the body.

Atoms and elements Molecules Compounds Cells Tissues Organs Organ system Organism

Warm up #7 Re-write the question and write your answer under it. 1. What are the 8 levels of organization from smallest to largest. 2. Describe what a organ system is and give an example of an organ system.

II. Discovering Cells O htm htm O Read through this description of the different cell theories over the years. Read years 1665, 1670, 1833, 1838, and O Write a description about what important findings each scientist discovered about the cell.

II. Discovering Cells a. Cells are the basic unit of structure and function for all living things b. The Structure of a living thing depends on the way cells are put together c. The function of an organism is the process by which it grows, lives, and reproduces

II. Discovering Cells d. Scientist i. Robert Hook: looked at a piece of a tree under a microscope noticed what looked like rectangular rooms 1. He called them cells, which means small rooms ii. Matthias Schleiden: concluded that plants were made of cells iii. Theodor Schwann: concluded that animals were made of cells iv. Rudolf Virchow: proposed that new cells are made from other cells

II. Discovering Cells e. Cell Theory i. This was made from the studies of the scientists ii. The Cell Theory says: 1. All living things are made of cells 2. Cells are the basic unit of structure and function in living things 3. All cells produce other cells

II. Discovering Cells f. Microscopes i. These are used for looking at cells ii. Two different types 1. Electron Microscope: These are used to see objects that are too small to be seen with a compound microscope 2. Compound Microscope: uses two lenses to look at small objects

III. Cells and Homeostasis a. Homeostasis: the maintenance of internal stability that is necessary for life functions i. Cells maintain homeostasis by receiving and using energy from food and removing waste b. How the cell gets energy i. The food that we eat gives our cells energy ii. The process that breaks down the food and gets energy from the food is called Cellular Respiration

III. Cells and Homeostasis 1. Cellular Respiration takes Glucose (which is a type of sugar) and turns it into energy by using oxygen 2. The waste products of this process are Carbon Dioxide and Water 3. Cellular Respiration Equation:

III. Cells and Homeostasis iii. Plants make their energy from a process called Photosynthesis 1. This uses sunlight, water and Carbon Dioxide to produce glucose within the cells for energy 2. The waste product of Photosynthesis is oxygen which is released out of the plant iv. What do you notice?

III. Cells and Homeostasis c. How the cell gets rid of its waste i. To maintain homeostasis the cell must rid itself of unwanted materials or waste ii. If these waste materials build up, they act as a poison to the cells and can start killing them off iii. Waste exits the cell through the Cell Membrane 1. This surrounds the outside of the cell 2. This is like the gatekeeper of the cell

III. Cells and Homeostasis iv. The process by which items move in and out of the cell is called Diffusion 1. Diffusion says that molecules will move from a higher concentration to a lower concentration 2. As molecules are moving they collide into one another and want to move away from each other. 3. Eventually, the molecules will be spread evenly throughout a space 4. Gases and water move easily across the cell membrane 5. Larger Molecules are harder to move across the cell membrane

III. Cells and Homeostasis d. Reproduction of Cells i. Cell Division is the process by which a cell creates another cell ii. These cells are genetically identical 1. Meaning they hold the same genes iii. Replication of cells helps to replace damaged cells, grow muscle cells and bone cells and much more. iv. Cell replication helps maintain homeostasis

Warm-Up #9 Re-write the Question and Answer in Complete Sentences 1. Why is Homeostasis important? 2. What is diffusion? 3. What part of the cell uses diffusion? 4. Why is Cellular Respiration important for our cells?

IV. Outer Parts of the Cell a. Cell Wall i. A rigid layer that surrounds the cells of plants. ii. This cell wall helps to give support and protection to the cell iii. Mostly made of Cellulose iv. Animal cells DO NOT have cell walls

IV. Outer Parts of the Cell b. Cell Membrane i. Found in both plant cells and animal cells ii. Controls what goes in and what comes out of the cell. iii. Mostly made of lipids iv. In Animal Cells this is the barrier between the cell and its environment

V. Inner Parts of the Cell a. These are called Organelles b. The Nucleus i. This is the control center of the cell ii. This hold the genetic information needed for the cell and body to grow and function iii. This is the largest organelle iv. Parts of the Nucleus 1. Chromatin: thin strands of DNA and proteins that fill up the inside of the nucleus 2. Nucleolus: small round structure found inside the nucleus

V. Inner Parts of the Cell c. The Ribosomes i. These produce proteins for your body d. The Cytoplasm i. Fills the cell and is a fluid like material ii. This moves constantly within the cell e. The Mitochondria i. Nicknamed the “powerhouse” of the cell ii. Cellular Respiration occurs within the mitochondria iii. Releases this energy into the cell for use

V. Inner Parts of the Cell f. The Endoplasmic Reticulum i. Also called the E.R. ii. Split into two parts 1. The Rough ER: contains Ribosomes 2. The Smooth ER: Has no Ribosomes iii. Helps Ribosomes make proteins iv. Sits right outside the nucleus

V. Inner Parts of the Cell g. The Golgi Body or the Golgi Apparatus i. Packs proteins and other materials to prepare for moving about the cell ii. Sits right beside the Endoplasmic Reticulum

V. Inner Parts of the Cell h. The Vacuole i. In Plants: normally have one large water filled vacuole ii. In Animals: some animals cell have vacuoles others do not iii. These store food, water, and other materials

V. Inner Parts of the Cell i. The Chloroplasts i. Found in plant cells ii. Are the site of photosynthesis iii. Captures sunlight and changes it to make food for the plant j. The Lysosome i. Breaks down materials and decides if it should be used again or thrown out