The Cell

What is a cell? The basic unit of structure and function of all living things. The basic building block of all organisms.

What are organelles? Humans have organs Cells contain organelles These organelles are like tiny organs inside a cell. For example: A nucleus acts like the brain of the cell. Nucleus

History Robert Hooke – first to discover cells. Looking at Cork under the microscope.

History Schleiden Botanist who said all plants are made of cells.

History Schwann Zoologist who said all animals are made of cells

History Virchow All living cells come only from other living cells.

Cell Theory All living things are made up of cells Cells are the basic units of structure and function of living things Living cells come only from other living cells.

What’s the difference anyway? Theory Tested and based on results, develop an idea that could explain the problem. Can be proven true or false by others Theory of Evolution, the BIG Bang Theory Law Doesn’t need to be tested, because we KNOW it to be true Each time, it has the same outcome The law of gravity

Organization of an organism

Basic Structures of a cell All cells share certain structures that make them a cell All cells must contain at least 4 basic structures to be considered a living cell Cell membrane Ribosomes -- DNA Cytoplasm

The Cell Cell Membrane: 1. ALL CELLS 2. Separates the cell from the outside environment 3. The membrane is what makes a cell… a cell.

The Cell Ribosomes: 1. ALL CELLS 2. Found in the cytoplasm & on E.R. 3. Proteins are made here from DNA instructions to carry out the functions of life

The Cell Cytoplasm: 1. ALL CELLS 2. The ENVIRONMENT of the cell. All organelles float in it

TWO TYPES OF CELLS PROKARYOTES – DO NOT contain a NUCLEUS or membrane bound organelles Ex: bacteria EUKARYOTES – DO CONTAIN A NUCLEUS and contain membrane bound organelles. Ex: animal and plant cells

The Cell Nucleus: 1. Animal & Plant Cells 2. Center of the cell Control Center of the cell

The Cell Cell Membrane: 1. Animal & Plant Cells 2. Controls the movement of material into & out of the cell 3. Selectively Permeable – chooses what enters and exits the cell

Cell transport - Diffusion the process by which molecules spread from areas of high concentration, to areas of low concentration Does not require Energy; happens naturally Passive Transport**** Equilibrium when the molecules are even throughout a space

Passive Transport: No energy Concentration Gradient - change in the concentration of a substance from one area to another.

Active Transport Requires Energy Low to high concentration

Osmosis 75 % of cells is water the diffusion of water (across a membrane) Water will move in the direction towards where there is a high concentration of solute (and hence a lower concentration of water) Does not require Energy; happens naturally

Endocytosis and Exocytosis Endo = In Exo = Out Sections of the membrane “swallow” substances and bring them into or out of the cell

Review: Producers Producers get their energy from the sun. Producers convert this light energy into stored chemical energy (glucose). This process is called photosynthesis.

Review: Consumers Consumers get their energy from the producers. Consumers convert stored chemical energy (glucose) into usable chemical energy (ATP). This process is called cellular respiration.

Cellular Respiration (aerobic) Cellular respiration is the process by which glucose (C6H12O6) is broken down to release energy for making ATP, another form of chemical energy.

Aerobic Respiration – Equation C6H12O6 + 6 O2 6 H2O + 6 CO2 + 36 ATP food (glucose, a carbohydrate) oxygen water carbon dioxide Does this look familiar?

Chemical Equations Photosynthesis: Aerobic Cellular Respiration: 6 H2O + 6 CO2 + energy (sun) → C6H12O6 + 6 O2 Aerobic Cellular Respiration: C6H12O6 + 6 O2 → 6 H2O + 6 CO2 + energy (ATP)

Why ATP? An analogy to money… Glucose in our food is a great source of energy! ($100 bill) However, individual cell processes may only require a small amount of energy ($1 bill) Analogy: most vending machines do not accept $100 bills! We need a smaller form of “currency” for these processes. ATP (adenosine triphosphate) is this important cellular “currency” for life. ATP releases more appropriate amounts of energy for the individual cellular processes that require energy.

Do only animals respire? Or do plants respire too? The BIG Question is… Do only animals respire? Or do plants respire too? Only plants perform photosynthesis Plants AND animals perform cellular respiration! (Can you explain why??)

Site of Cellular Respiration Plant and animal cells contain mitochondria: cell structures that transform chemical energy from glucose to ATP.

Significant ATP Production Aerobic cellular respiration releases energy SLOWLY, using oxygen to convert ONE molecule of glucose to 36 ATP!

Cellular Metabolism & Energy Cellular Respiration Process where organisms use food to make usable energy for cells Step 1: Glucose is broken down in the cytoplasm Step 2: Oxygen helps Energy captured to be changed into ATP for cellular use in the mitochondria

The Cell Mitochondria: 1. Animal & Plant Cells 2. RESPIRATION occurs here (use of oxygen to break down food particles for energy) 3. Makes ENERGY for the cell.

2 types of Cellular Respiration Aerobic Respiration Requires Food & Oxygen Water and CO2 are waste products Food + Oxygen CO2 + Water + ATP Energy not used is stored as fat

2 Types of Cellular Respiration Anaerobic Respiration (Fermentation) Does not require Oxygen (anaerobic) Yeast cells used to make bread Creates CO2 (makes bread rise) , alcohol (for beer, wine, champagne)

The Cell Vacuoles: 1. In Plants (LARGE) & Animal 2. Floating in the cytoplasm FOOD, WATER, and Waste are STORED here

The Cell Lysosomes: 1. Mostly Animal 2. Floating in the cytoplasm Digests food or Recycles old or dead cell parts

Protein Synthesis

Protein Production Process where organisms use the instructions in DNA to make proteins for specific jobs in or outside the cell Step 1: DNA is translated into a protein by the ribosomes Step 2: Proteins are processed and transported in the ER and packaged in movable vacuoles called vessicles and shipped to needed locations inside/outside the cell by the golgi bodies.

The Cell Ribosomes: 1. Animal & Plant Cells 2. Found in the cytoplasm & on E.R. Proteins are made here Using instructions from DNA

The Cell Endoplasmic Reticulum (E.R.): 1. Animal & Plant Cells 2. Found around the nucleus and throughout the cytoplasm 3. Transports materials in the cell (TRANSPORTATION SYSTEM)

The Cell Golgi bodies: 1. Animal & Plant Cells 2. Floating in Cytoplasm 3. Package & Ships cell materials

Major differences between a plant and animal cell Plant cells have a cell wall – animal cells do not. Plant cells have chloroplasts – animal cells do not Plant cells have a much larger vacuole than animal cells Animal cells have lysosomes, plants do not

The Cell Chloroplast: 1. Plant Cells 2. Floating in Cytoplasm 3. Makes food for cell (Photosynthesis – captures ENERGY IN SUNLIGHT) 4. Contains CHLOROPHYLL To absorb sunlight

The Cell Cell Wall: 1. Plant Cells – NOT IN ANIMALS!! 2. Gives plant cells its shape STRONG to provide Structure and support

Lysosomes You will find organelles called lysosomes in nearly every animal-like eukaryotic cell. They hold enzymes that digest ot break down food or worn out cell parts.

Cellular Metabolism & Energy Photosynthesis Process where plants use light for food Step 1: Energy in the form of sunlight is captured by the chlorophyll in the chloroplast Step 2: Energy captured is changed into food for plant

Photosynthesis REMEMBER – PLANTS STILL COMPLETE RESPIRATION! Sunlight + CO2 + Water Glucose (food) + O2 REMEMBER – PLANTS STILL COMPLETE RESPIRATION!

2 3 1 4 5 6 10 7 9 8 Review: Is this a plant or animal cell? Label the numbers 2 3 1 4 5 6 10 7 9 8

The Cell 1 2 3 4 5 Nucleolus 10 6 9 Cytoplasm 7 8

Ticket at the door – 5 points Number your paper from 1 – 5. Answer the questions. What two organelles are unique to plant cells? Does a prokaryotic cell have a nucleus? Yes or no Does active transport require energy? Yes or no What two things are needed to preform cellular respiration? Do all cells preform cellular respiration? Yes or no