What is life? The characteristics of living things The characteristics of living things What is an organism? Give a few examples. What is an organism? Give a few examples. 6 important characteristics: 6 important characteristics: 1.All organisms are made of cells A cell is the basic unit of structure (the way it’s made) and function (the job it performs). A cell is the basic unit of structure (the way it’s made) and function (the job it performs). Cells are similar in being the basic building blocks of animal and plant tissues. They are composed of complex chemicals and can perform tasks necessary to life. Cells are similar in being the basic building blocks of animal and plant tissues. They are composed of complex chemicals and can perform tasks necessary to life. Who can give an example of a multicellular organism? What about a unicellular organism? Who can give an example of a multicellular organism? What about a unicellular organism? 1.Made of cells 4.Grow and develop 2.Contain similar chemicals 5.Respond to their surroundings 3.Use energy 6.Can reproduce

What is life? 2.Cells contain similar chemicals The most abundant chemical in a cell is water The most abundant chemical in a cell is water Carbohydrates are the main energy source Carbohydrates are the main energy source Proteins and lipids are the building materials Proteins and lipids are the building materials Nucleic acids are the genetic material (the instructions that direct cell’s activities) Nucleic acids are the genetic material (the instructions that direct cell’s activities) 3.Cells use energy to do what living things must do As you sit there, your eyes and brain are busy learning, your stomach and intestines are digesting food, your cells may be repairing themselves, etc. As you sit there, your eyes and brain are busy learning, your stomach and intestines are digesting food, your cells may be repairing themselves, etc. 4.Living things grow and develop Who can describe growth and development? Who can describe growth and development? Growth is the process of becoming larger. Development is the process of change that occurs during an organism’s life to produce a more complex organism. Growth is the process of becoming larger. Development is the process of change that occurs during an organism’s life to produce a more complex organism. To grow and develop, energy is used to create new cells To grow and develop, energy is used to create new cells

What is life? 5.All organisms react to changes in their environment A stimulus is a change in an organism’s surroundings that causes it to react. The response is the reaction. A stimulus is a change in an organism’s surroundings that causes it to react. The response is the reaction. Who can explain and give examples of external versus internal stimuli? Who can explain and give examples of external versus internal stimuli? 6.All organisms have the ability to reproduce, or produce offspring that are similar to the parents How do growth and development differ? How do growth and development differ? Life comes from life – proved by Redi & Pasteur Life comes from life – proved by Redi & Pasteur The mistaken idea that living things arise from non-living things is called spontaneous generation The mistaken idea that living things arise from non-living things is called spontaneous generation

What is life? Living things must satisfy their basic needs for energy, water, living space and stable internal conditions Living things must satisfy their basic needs for energy, water, living space and stable internal conditions Some organisms use food as their energy source; they use the sun’s energy along with carbon dioxide & water to make their food Some organisms use food as their energy source; they use the sun’s energy along with carbon dioxide & water to make their food How do heterotrophs depend on autotrophs for energy? How do heterotrophs depend on autotrophs for energy? Heterotrophs can not produce their own food, so they obtain their energy from the food they eat. They either eat autotrophs and obtain the energy stored in the food made by the autotrophs, or they eat other heterotrophs that eat the autotrophs. Heterotrophs can not produce their own food, so they obtain their energy from the food they eat. They either eat autotrophs and obtain the energy stored in the food made by the autotrophs, or they eat other heterotrophs that eat the autotrophs.

What is life? Water is required to obtain chemicals from surroundings, break down food, grow, move substances within their bodies and reproduce Water is required to obtain chemicals from surroundings, break down food, grow, move substances within their bodies and reproduce Organisms need a place to live and may compete for it Organisms need a place to live and may compete for it What advantage do animals have over plants in terms of living space? What advantage do animals have over plants in terms of living space? Homeostasis allows for the maintenance of stable internal conditions Homeostasis allows for the maintenance of stable internal conditions Who can provide some examples of homeostasis? Who can provide some examples of homeostasis? The human body’s regulation of temperature The human body’s regulation of temperature Barnacles can close up it’s hard outer plates, trapping droplets of water inside to keep its body moist until the next high tide Barnacles can close up it’s hard outer plates, trapping droplets of water inside to keep its body moist until the next high tide

Discovering Cells Around 1590, the invention of the microscope made it possible for people to discover and learn about cells Around 1590, the invention of the microscope made it possible for people to discover and learn about cells A simple microscope has one lens (like a hand lens), a compound microscope has multiple lenses A simple microscope has one lens (like a hand lens), a compound microscope has multiple lenses Robert Hooke, Anton van Leeuwenhoek, Matthias Schleiden & Theodor Schwann and other important scientists - their findings led to the cell theory Robert Hooke, Anton van Leeuwenhoek, Matthias Schleiden & Theodor Schwann and other important scientists - their findings led to the cell theory

Discovering Cells The cell theory states: The cell theory states: All living things are composed of cells All living things are composed of cells Cells are the basic unit of structure and function in living things Cells are the basic unit of structure and function in living things All cells are produced from other cells All cells are produced from other cells This theory holds true for all living things, regardless of size or complexity, since all living things are made of cells This theory holds true for all living things, regardless of size or complexity, since all living things are made of cells

Discovering Cells Light Microscope Light Microscope 2 important properties of microscopes are magnification and resolution 2 important properties of microscopes are magnification and resolution The lens or lenses in a light microscope magnify an object by bending the light that passes through them The lens or lenses in a light microscope magnify an object by bending the light that passes through them The microscopes used by the early scientists were all light microscopes The microscopes used by the early scientists were all light microscopes Electron Microscope Electron Microscope Use a beam of electrons instead of light to examine a specimen Use a beam of electrons instead of light to examine a specimen Has much better resolution than a light microscope Has much better resolution than a light microscope

Discovering Cells How did the invention of the microscope affect scientists’ understanding of living things? How did the invention of the microscope affect scientists’ understanding of living things? It made it possible for people to discover and learn about cells It made it possible for people to discover and learn about cells Explain the 3 main ideas of the cell theory. Explain the 3 main ideas of the cell theory. According to the cell theory, all living things are made of cells, cells are the basic building blocks of life, and they are the only source of new cells. According to the cell theory, all living things are made of cells, cells are the basic building blocks of life, and they are the only source of new cells. How does a compound microscope use lenses to magnify an object? How does a compound microscope use lenses to magnify an object? Light passing through the first lens magnifies the object; then light passing through the second lens magnifies the image of the object even more. Light passing through the first lens magnifies the object; then light passing through the second lens magnifies the image of the object even more. Explain why both magnification and resolution are important when viewing a small object with a microscope. Explain why both magnification and resolution are important when viewing a small object with a microscope. Magnification makes an object larger while resolution sharpens the image Magnification makes an object larger while resolution sharpens the image

Looking Inside Cells Cells contain tiny cell structures called organelles, which carry out specific functions in the cell Cells contain tiny cell structures called organelles, which carry out specific functions in the cell Cells of plants and other organisms have cell walls; the cells of animals and other organisms lack cell walls Cells of plants and other organisms have cell walls; the cells of animals and other organisms lack cell walls What is the function of the cell wall? What is the function of the cell wall? To help protect and support the cell To help protect and support the cell All cells have cell membranes – the structure you pass right after passing through the cell wall All cells have cell membranes – the structure you pass right after passing through the cell wall Explain the function of the cell wall. Explain the function of the cell wall. Controls what substances come into and out of a cell Controls what substances come into and out of a cell The nucleus is the cell’s brain or control center, directing all of the cell’s activities The nucleus is the cell’s brain or control center, directing all of the cell’s activities

Looking Inside Cells Inside the Nucleus: Inside the Nucleus: Nuclear membrane – similar to the cell membrane Nuclear membrane – similar to the cell membrane Chromosomes – formed when chromatin strands coil and condense. Chromatin contains the genetic material. Chromosomes – formed when chromatin strands coil and condense. Chromatin contains the genetic material. Nucleolus – where ribosomes are made. Ribosomes are the organelles where proteins are produced. Nucleolus – where ribosomes are made. Ribosomes are the organelles where proteins are produced. Outside of the Nucleus: Outside of the Nucleus: *Check your ch 4 key terms for definitions* *Check your ch 4 key terms for definitions* Mitochondria Mitochondria Endoplasmic Reticulum Endoplasmic Reticulum Ribosomes Ribosomes Golgi Bodies Golgi Bodies Chloroplasts Chloroplasts Vacuoles Vacuoles Lysosomes Lysosomes

Looking Inside Cells Bacterial cells Bacterial cells Smaller than plant and animal cells Smaller than plant and animal cells Does not contain a nucleus – prokaryotes. (those that do contain a nucleus plus the other organelles are eukaryotes) Does not contain a nucleus – prokaryotes. (those that do contain a nucleus plus the other organelles are eukaryotes) Genetic material is found in the cytoplasm Genetic material is found in the cytoplasm Contain ribosomes, but none of the other organelles found in plant and animal cells Contain ribosomes, but none of the other organelles found in plant and animal cells Structure & Function of cells – similar to the structure & function of organisms Structure & Function of cells – similar to the structure & function of organisms The bodies of many multicellular organisms have four levels of organization The bodies of many multicellular organisms have four levels of organization Cells  tissues  organs  organ systems Cells  tissues  organs  organ systems Describe each of the levels that complex organisms exhibit Describe each of the levels that complex organisms exhibit

Looking Inside Cells Choose one of 2 activities: Choose one of 2 activities: Create a model of the animal or plant cell (or both) Create a model of the animal or plant cell (or both) You can draw and color it, or use colored paper to create the pieces and fit it all together You can draw and color it, or use colored paper to create the pieces and fit it all together Create a key that identifies what each of the organelles are and what their function is Create a key that identifies what each of the organelles are and what their function is Use pages 142 – 143 as guidelines Use pages 142 – 143 as guidelines A cell is similar to the human body – match the cell’s organelles to human body parts that carry out similar functions. A cell is similar to the human body – match the cell’s organelles to human body parts that carry out similar functions. For example, the cell’s nucleus would be like the human brain. For example, the cell’s nucleus would be like the human brain. Also, develop a way that will help students link the organelle to it’s specific function. Also, develop a way that will help students link the organelle to it’s specific function.

Introduction to Genetics Traits are the physical characteristics that an organism can pass on to its offspring Traits are the physical characteristics that an organism can pass on to its offspring Describe traits of humans? What about traits of plants? Describe traits of humans? What about traits of plants? Remember that chromatin contains genetic material that directs the cell’s activities Remember that chromatin contains genetic material that directs the cell’s activities This genetic material also plays a role in heredity This genetic material also plays a role in heredity Organisms resemble their parents because they inherit genetic material from their parents. Organisms resemble their parents because they inherit genetic material from their parents. DNA, or deoxyribonucleic acid, carries info from the parent to the offspring DNA, or deoxyribonucleic acid, carries info from the parent to the offspring A gene is a section of DNA that controls an inherited trait A gene is a section of DNA that controls an inherited trait

Introduction to Genetics Bacteria produce asexually by dividing into 2 cells Bacteria produce asexually by dividing into 2 cells The genes are identical to the parent organism The genes are identical to the parent organism Other organisms such as plants and animals produce sexually Other organisms such as plants and animals produce sexually New organisms result from the combination of genetic material from 2 parent organisms New organisms result from the combination of genetic material from 2 parent organisms The traits are determined by genetic material from both the male and female parents The traits are determined by genetic material from both the male and female parents Genetic material is re-sorted, over and over, each time reproduction occurs  this is why you resemble your parents more than your grandparents or great- grandparents Genetic material is re-sorted, over and over, each time reproduction occurs  this is why you resemble your parents more than your grandparents or great- grandparents Why aren’t the offspring of sexually reproducing organisms identical to either of their parents? Why aren’t the offspring of sexually reproducing organisms identical to either of their parents?

Introduction to Genetics In selective breeding, organsims that have certain desired traits are mated to produce offspring with the desired traits of both parents. The desired traits are produced by the combination of genetic material that the offspring inherit from both of their parents. In selective breeding, organsims that have certain desired traits are mated to produce offspring with the desired traits of both parents. The desired traits are produced by the combination of genetic material that the offspring inherit from both of their parents. Explain why selective breeding would be important to someone. Explain why selective breeding would be important to someone. Traits of organisms can change over generations naturally  this is necessary to help organisms survive better in their environment Traits of organisms can change over generations naturally  this is necessary to help organisms survive better in their environment