1. Chapter 4 Honors and Lab Biology

2.  Quick Write : ◦ Why do we need to learn about cells?

3. Healing time is radically reduced and scarring almost eliminated by bioartificial skin!

4.  Cells that do NOT contain membrane bound organelles. (unicellular)

5. Cells that DO contain membrane bound organelles.

6.  Cells were discovered due to microscopes in the early 17 th century  ROBERT HOOKE 1665 (english scientist) examined a slice of cork, he saw “little boxes” they reminded him of small rooms….cells! These were dead plant cells.  ANTON VAN LEEUWENHOEK 1632-1723 (dutch microscope maker) first to observe living cells

7.  Is the smallest unit of matter that can carry out all the processes of life.  Organelle: parts within a cell!

8.  1. All living things are composed of one or more cells  2. Cells are the basic unit of structure and function in an organism  3. Cells come from the reproduction of existing cells.

9.  Matthias Schleiden (1838) botanist, all plants are composed of cells  Theodor Schwann (1839) zoologist, all animals are composed of cells  Rudolf Virchow (1855) physician, cells come ONLY from other cells.

10.  Not all cells are alike! They vary in… ◦ A) size ◦ B) shape ◦ C) internal organization SIZE: range from.2m – 0.2um (most are 10-50um) -not all are microscopic (most are) ex: giraffe’s nerve cells extend 6.5 ft. down it’s leg!! Cells are limited in size by the ratio between their outer surface area and their volume

11.  Organelles: parts of a cell, have specific jobs  Tissues: groups of cells that have a similar function

12. !!

15.  Organ systems- a group of organs that work together to perform a set of related tasks. Digestive system includes: the stomach, esophagus, intestines and mouth.  Cells → Tissues → Organs → Organ Systems

17.  Cell Membrane – separates cell from external environment, gives shape and flexibility to cell, selectively permeable

18.  Cytoplasm: ◦ gelatin like aqueous fluid called cytosol ◦ Cytoplasmic streaming ◦ Mostly water but also salts and organic molecules

19.  Mitochondia: power house of the cell! Where cellular respiration occurs, production of ATP, has it’s own DNA ◦ Cristae: inner membrane creating many folds to increase surface area

20.  Ribosomes: where proteins are made, ◦ Free Floating Ribosome: make proteins for the cell ◦ Ribosomes attached to ER: make proteins to be exported from the cell

21.  Endoplasmic Reticulum: (ER) acts as a highway for molecules to move around the cell. ◦ Smooth ER: does NOT contain ribosomes ◦ Rough ER: does contain ribosomes

22.  Golgi Apparatus (bodies) processes, packages, and secretes  a) product is assembled (moves from ER to golgi, where it is put together and adjusted)  b) product is packaged (in new sacs)  c) product is mailed out (sent out of cell)

23.  Cilia: short hair like projections beat together to move an organism ex: humans trachea cilia move fluids and mucus! YUM

24.  Flagella: long, whiplike projections, single or in pairs, rapid movement, ex: sperm

25.  Nucleus: brains! Control center of cell, DNA & RNA are made here! ◦ Nuclear envolope: double membrane with pores ◦ Chromatin: fine strands of DNA & protein ◦ Nucleolus: inside nucleus where ribosomes are made

26.  Lysosome: digestive enzymes, digest food, disease causing bacteria, old organelles, ex: lysosomes eat up tissue between fingers in embryos, usually only in animal cells

27.  Cytoskeleton- helps shape & support cells ◦ Microtubules: long slender protein tubes form spindle fibers during mitosis ◦ Microfilaments: fine protein threads

28.  Centrioles: cell reproduction  Centrosome: cell reproduction

30.  Cell Wall: rigid covering made of cellulose, protects cell, goes OUTSIDE cell membrane

31.  Central Vacuole: huge structure which may take up 90% of the space in plant cell

32.  Plastids ◦ a) chloroplasts : site for photosynthesis ◦ b) chromoplasts: stores red and yellow pigment ◦ c) leucoplasts: non pigmented