Carrying Out Life Processes EQ: How are life processes carried out by unicellular and multicellular organisms?

Life Processes O A process is a series of steps taken to achieve an outcome. O All organisms perform certain processes to obtain oxygen, obtain food, to remove wastes, and to grow. O Photosynthesis, cellular respiration, diffusion, osmosis, mitosis are all life processes carried out by all organisms

Unicellular vs. Multicellular O An organism can be defined as living being that shows all six of the characteristics of life. O Growth, reproduction, responds to environment, uses energy, composed of cells, has DNA

Unicellular Organisms O Some living organisms are made of one cell only, and are called unicellular. O These organisms have a large surface area to volume ratio and rely on simple diffusion to meet their needs. O All life processes are performed by the organelles within the cell

Unicellular Organisms O An example of a unicellular organism is the paramecium. O A paramecium is a small one celled living organism that has all six characteristics of living things and can carry out life processes. O Useful substances that the paramecium requires like oxygen passes into to the paramecium from the environment by diffusion and waste substances pass out into the environment also via diffusion.

Multicellular Organisms O Multicellular organisms are those which are made up of many cells. O Humans are multicellular. O Multicellular organisms can be much larger and more complex. O This is because the cells of the organism have specialized into many different types of cells such as nerve cells, blood cells, muscle cells all performing different functions.

Multicellular Organisms O Furthermore, the specialized cells make up tissues, tissues make up organs, and organs make up organ systems. O OCTOSO

Unicellular vs. Multicellular Unicellular Multicellular O Simple body construction (single cell) O All functions carried out by the organelles of the single cell O Does not achieve large size O Short life span O No cell specialization O Tend to be microscopic O Complex organization O Specific functions for different cells O Cell specialization, O Can increase size by increasing the number of cells O Longer life span O Tend to be macroscopic (seen with naked eye)

UnicellularMulticellular

Balancing The Systems EQ: How do organ systems work together to enable an organism to maintain homeostasis?

Systems O A group of organs that work together and provide an organism with an advantage for survival is called a system.

Systems O Systems are the most complex organizational level in your body. O OCTOSO O Systems are made of individual organs, such as the heart or lungs O Systems work alone and with other systems to allow your body to maintain homeostasis

Homeostasis O Homeostasis is a stable internal environment that allows you (and your cells to survive) O All of your body’s systems work together to maintain homeostasis inside your body

Homeostasis O Homeostasis is achieved by making sure the temperature, ph (acidity), oxygen levels, and many other factors are set just right for your cells to survive.

Your systems must work together to achieve homeostasis O All systems in an organism are interconnected. O For example: the circulatory and respiratory systems O As blood circulates through your body, it needs fresh oxygen from the air. O When the blood reaches the lungs, part of the respiratory system, the blood is reoxygenated.

Examples of systems O Circulatory O Skeletal O Muscular O Respiratory O Digestive O Excretory O Intergumentary O Nervous O Lymphatic O Endocrine

Today’s task O You will be placed in a small group and assigned an organ system. O You are to use the packets provided to find the following information so that we may complete the graphic organizer on the board O Major organs of the system O The purpose/functions of the system O How your system interacts with other systems O Other critical information