Intro to Organ Systems

Describe how tissues and organs are formed. Describe the organization of cells into tissues, tissues into organs, and name key organs in systems. Describe key function of organs.

Cells We know that life is built to cells. The way we look is the result of the types of cells we are made of and how they are arranged or organized. Take a look at an animal cell and a plant cell. There is no wonder why we look very different.

From Simple to Complex 2 x 6 piece of lumber Lots of lumber A wall Many walls and a roof house

From Simple to Complex Cell Tissue Organ Organ System Human Body

Cells The basic unit of structure and function of all living things. Three major parts: –Cell membrane – selective and semipermeable –Nucleus – the control center of the cell; it has a nuclear membrane around it and contains the nucleoli and DNA –Cytoplasm – semifluid material between the cell membrane and the nucleus. Embedded in the cytoplasm are organelles that help a cell to function. Organelles include the centrosomes, ribosomes, golgi apparatus, endoplasmic reticulum, mitochondria, lysosomes, cytoskeleton, and peroxisomes.

Functions of organelles Centrosomes Endoplasmic reticulum Mitrochondria Golgi apparatus Lysosomes Ribosomes Peroxisomes Cytoskeleton (look these up)

Cell Division Mitosis Meiosis

Cell Movement Passive processes: –Diffusion – molecules move from an area of greater concentration to lesser concentration. (they scatter and dissolve and then are known as solutes.) When molecules are evenly distributed, this is know as equilibrium. hill.com/sites/ /student_view0/chapter2/animation__how_diffusion_works.html hill.com/sites/ /student_view0/chapter2/animation__how_diffusion_works.html –Osmosis – diffusion of water across a semipermeable membrane from an area of higher concentration to a lower concentration. Selective because some things permeate and others don’t. –Filtration – solutes and water move from higher pressure area to that with a lower pressure…usually with the help of gravity or mechanical force. (membrane pores dictate size of molecules filtered.)

Cell Movement Active processes: –Active transport – molecules move across a cell membrane from lower to higher concentration this requires ATP supplied by cell metabolism. –Phagocytosis – “cell eating” – substances engulfed by the cell membrane. When the substance is totally inside the vacuole, enzymes from the cytoplasm digest it. –Pinocytosis – “cell drinking” – the cell ingests these molecules for its own nutrients.

Tissue to Organ Each specific cell Is grouped with cells similar in structure and function. We call this a tissue. Tissues link together to carry out a specific function.

Tissues Cells of the same type joining together for a common purpose. 99% water with various dissolved substances and is slightly salty (tissue fluid). If there is not enough tissue fluid this can lead to dehydration…too much can lead to edema.

Types of Tissues Epithelial tissue Connective tissue Muscle tissue Nervous tissue Covers the body and lines the intestine, respiratory, circulatory, and urinary systems. Supporting fabric of body. Soft = adipose, ligaments and tendons…hard = cartilage and bone. Made up of neurons…brain, spinal cord, and nerves. Produces power and movement. Skeletal, cardiac, and smooth.

Organs and Systems A. Integumentary system B. Skeletal system C. Muscular system D. Nervous system E. Special senses F. Circulatory system G. Lymphatic system H. Respiratory system I. Digestive system J. Urinary system K. Endocrine system L. Reproductive system

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