BIOLOGY AND GEOLOGY 3º DE E.S.O. Chapter 1: The organisation of the human body
1. INTRODUCTION: LEVELS OF ORGANISATION What is a cell?
Definition of Cell A cell is the smallest unit that is capable of performing life functions.
Which are the life functions? http://www.edistribucion.es/anayaeducacion/8420042/sc1_uni3/ unit_03_video_02.html
The three vital functions are Nutrition: living things obtain matter and energy in order to survive Interaction: living things are able to sense changes in their environment and react in order to survive Reproduction: living things produce descendants that maintain their characteristics
Cell Theory All living things are made up of cells. Cells are the smallest working units of all living things. All cells come from preexisting cells through cell division.
Examples of Cells Bacteria Plant Stem Red Blood Cell Nerve Cell
https://www.youtube.com/watch?v=68_0jlzzlr0 Cells may have the DNA https://www.youtube.com/watch?v=urujd5nexc8 in the cytoplasm or Prokaryotic cells Enjoy travelling inside a cell. Is it eukaryotic or prokaryotic? inside a nucleus Eukaryotic cells http://www.youtube.com/watch?v =2KQbVr9kFO0&feature=related
Prokaryotic cells DNA in the cytoplasm Plasmatic membrane and cellular wall They don t have organelles except ribosomes Some of them have an autotrophic nutrition, other have an heterotrophic nutrition They may use either a flagellum or many cilia to move http:// www.youtube.com/watch?v =dxvg-dwotku Prokaryotes include the domains Bacteria
Eukaryotic cells DNA in the nucleus They have a great variety of organelles in the cytoplasm (vacuoles, mitochondria, ribosomes, ) Some of them have an autotrophic nutrition, other have an heterotrophic nutrition Eukaryotes include the domain Eukariote with four kindoms: plants, animals, fungi, protista
Typical Animal Cell Typical Plant Cell
2. HUMAN CELL Which type of cells make up your body?
Animal Cell Parts: 2.1 CELL MEMBRANE 2.2 NUCLEUS 2.3 CYTOPLASM https://www.youtube.com/watch?v=g4l_qo4wktm
2.1 Surrounding the Cell: Cell Membrane Structure: very thin double layer that covers the cell Function: controls which substances go in and out
2.2 Nucleus Structure: Separated from cytoplasm by nuclear membrane Contains genetic material DNA Holds the nucleolus Function: Controls the activities of the cell
Nuclear Membrane Surrounds nucleus Made of two layers Pores allow material to enter and leave nucleus
DNA Complex chemical substance in which genetic information is contained
Chromosomes During cell division DNA is condenses in tiny packs called chromosomes
Chromatin When nucleus is no dividing the DNA appears as tiny granules called chromatin
Nucleolus Inside nucleus Contains RNA to build proteins
2.3 Cytoplasm Structure: Gel-like mixture which fill the cell Surrounded by cell membrane Contains organelles: mitochondria, ribosomes, endoplasmatic reticulum, Golgi body, membranous vesicle, lysosomes, cytoskeleton and centrioles
2. CELL ORGANELLES
Mitochondria Structure: Double membrane. Function: Cellular respiration
Ribosome Structure: Each cell contains thousands Are composed of two sub-units Function: Makes proteins
Endoplasmic Reticulum Structure: Is formed by a series of interconnected sacs and canals Smooth type: lacks ribosomes Rough type (pictured): ribosomes embedded in surface Function: SER stores and moves materials in the cell RER +make proteins
Golgi Bodies Structure: Membranous sacs, from which vesicles emerge Function: Move materials within the cell Move materials out of the cell
Membranous vesicle (vacuoles) Structure Small membranous sacs. Traditionally, they were called vacuoles Function Stores nutrients and waste substances
Lysosome Structure Small vesicles that are generated in the Golgi body Function Celular digestion
Cytoskeleton Structure Long and thin filaments which extend around the cytoplasm Function Holds the organelles Gives shape to the cell Takes part in cellular movements
Centrioles Structure Two hollow cylinders composed of filaments Function Organize the separation of chromosomes during cell division Take part in the formation of filaments (cilia and flagella)
2.4 CELL DIFFERNTATION The process that a cell changes its shape and structure to carry out an specific function.
3. Human tissues Cells combine to form tissues A tissue is a group of cells organized to perform a specific function
Cells combine to form four primary tissues
Watch this video and answer the questions about the tissues http://www.youtube.com/watch?v=tkwtj3_-1e8
EPHITHELIAL TISSUE This tissue covers the external surface of body, forming the skin, and cavities and tracts such as the stomach and the intestines
MUSCLE TISSUE This tissue contracts and relaxes moving the body
NERVE TISSUE Nerve tissue is made up of neurons, which coordinate the functions of all the organs
CONECTIVE TISSUE Their function in the body is to connect and support. There are five types of connective tissue: conjunctive tissue, cartilaginous tissue, adipose tissue, bone tissue and blood tissue.
CONJUNTIVE TISSUE Conjunctive tissue is a type of connective tissue which joins the other tissues together
CARTILAGINOUS TISSUE This is a type of connective tissue which forms part of the skeleton and provides support to the soft parts of the body.
ADIPOSE OR FATTY TISSUE This is a type of connective tissue which provides energy reserve and thermal insulation to the body
BONE TISSUE Bone tissue is a type of connective tissue that provides support to the organism and protects the vital organs.
BLOOD TISSUE Transports oxygen, nutrients, waste substances and carbon dioxide; regulates the temperature and defends our body from infections.