Life Characteristics

Objective: You will be able to differentiate between living and nonliving things. Do Now: Read the introduction on top of page 16 Define biology

Characteristics of living things Made up of cell(s) Grow and develop Reproduce Obtain and use energy and materials Respond to the environment Maintain a stable internal environment Based on a genetic code As a group, change over time

Objective: You will be able to identify cells using a compound light microscope. Do Now: Read “Made up of cells” on p. 17 How many different cells are found in the human body?

Living things and cells All living things are made up of one or more cells Cells are the functional unit of living things Some organisms have only one cell and are called unicellular Some are even made up of trillions of cells

Do you smell what the Rock’s cooking?

Living things grow and develop Unicellular creatures simply increase their cell size Multicellular organisms go through growth called development Development begins with a fertilized egg that divides into different types of cells This is called differentiation because it makes different types of cells

Objective: You will be able to explain how reproduction can create offspring that are similar and different. Do Now: Read “Reproduction” on p. 17 Differentiate between sexual and asexual reproduction

Reproduction Is the creation of a new individual Can be done by: Sexual reproduction Asexual reproduction

Types of reproduction Sexual involves cells from two different parents combining Offspring are not exactly like either parent Asexual involves one parent creating offspring Offspring are usually identical to parent

Based on a genetic code Explains how offspring inherit traits from parents Traits are characteristics passed from one generation to the next DNA is a molecule that carries the traits from parent to offspring It is called the hereditary material

DNA

Do you smell what the Rock’s cooking!

How many different letters are there?

Paired Activity View several hydra under the microscope Draw a hydra and label the parent and the offspring Write a sentence that compares the offspring to the parent How does the hydra know how to make another hydra and not a monkey?

Objective: You will be able to explain the reason why organisms must consume food. Do Now: Read “Need for material and energy” on p. 18 List the reasons that organisms need materials and energy

Obtain and use materials and energy Food is energy Organisms take in material for energy Some organisms eat (heterotrophs) Some take in water and carbon dioxide to make their own food (autotrophs) They use this energy to do chemical reactions to stay alive and grow All of the chemical reactions involving energy to keep organisms alive is called metabolism

Paired activity You will be given nutritional facts about McDonalds and Subway Choose a typical meal you would have at each place Compare your choices with the daily recommended diet (below) Compare fats, protein, carbohydrates and calories Choose 1 complete meal from each restaurant that would not exceed the daily recommended diet.

Response to the environment Organisms detect and respond to stimuli A stimulus is a signal which causes an organism to respond Ex. Bright light, predator These are examples of external stimuli A stimulus can also be internal Ex. Too much CO2 in blood Organisms must respond to the environment to maintain homeostasis

Maintain a stable internal environment Even with changing external environment, most organisms must keep internal conditions stable Examples: Body temperature Blood sugar levels

Objective: You will be able to explain how favorable traits increase in a population. Do Now: Read “Evolution” on p. 20 Why can’t individuals evolve?

Organisms change over time Individuals don’t change over time but groups do change This change over time is called evolution Over thousands of years, these changes can become significant Explains the diversity of life

Adaptations Favorable traits that allow the organism to survive is called an adaptation Question What would happen if an individual was born with a new adaptation? Favorable traits (adaptations) increase in a population over time. Continues to increase until all individuals have it So overall, all of the organisms did change

What do you know? List 3 things you already know about evolution List 2 things you know about human evolution There are no right or wrong answers.

Objective: You will be able to list the levels of organization of life. Do Now: Read “Branches in Biology” on p. 20

Organization levels Biologists break life down into different levels This make sit easier to study life The order from smallest to largest Cells, tissues, organs, organ systems and organism

Cells make up living things

Tissues are groups of cells that work together

Organs are made of tissues working together

Organ systems are made of organs that work together

Organism is made of a group of organ systems working together

Paired Activity Chose one of the tissue slides Locate a cell of that tissue under high power Draw the cell and list what tissue it came from Repeat this until you have viewed four different tissue slides