chapter 2

science

Photosynthesis

process by which most plants, some protists, and many types of bacteria make their own food.

Cell membrane

protective outer covering of all cells that regulates the interaction between the cell and the environment.

Cytoplasm

constantly moving gel

Cell wall

ridged structure that encloses, supports, and protects the cells of plants, algae,fungi,and most bacteria.

Organelle

structure in the cytoplasm of a eukaryotic cell that can act as a storage site, process energy, move materials, or manufacture substances.

Nucleus

organelle that controls all the activities of a cell and contains hereditary material made of proteins and DNA; positively charged,central part of an atom.

Chloroplast

green, chlorophyll

Mitochondrion

cell organelle that breaks down food and releases energy.

Ribosome

small cytoplasmic structure on which cells make their own proteins.

Endoplasmic reticulum

cytoplasmic organelle that moves materials around in a cell and is made up of a complex series of folded membranes; can be rough (with attached ribosomes) or smooth (without attached ribosomes).

Golgi body

organelles that package cellular materials and transport them within the cell or out of the cell.

Tissue

group of similar cells that work together to do one job.

Organ

structure, such as the heart, made up of different types of tissues that all work together.

Magnify:

to increase the size of something

Cell theory

states that all organisms are made up of one or more cells, the cells is the basic unit of life, and all cells come from other cells.

Disease

a condition that results from the disruption function of one or more of an organism’s normal processes.

Virus

a strand of hereditary material surrounded by a protein coating.

Host cell

living cell in which a virus can actively multiply or in which a virus can hide until activated by environmental stimuli.

lysosomes

Organelle that contains digestive cheimicals that help break down food molecules, cell waste, and worn-out cell parts

Vacuole

an organelle used for temporary storage of water, waster products, food, and other cellular materials

Robert Hooke (1665)

Discovered cells when he looked at a thin slice of cork under an improved microscope (little empty boxes called cells)

Antonie van Leeuwenhoek (1600’s)

made a microscope with a tiny bead of glass for lens (beasties) microscope could magnify 270x

Robert Brown (1833)

An english botanist that discovered the nucleus in a plant cell

Matthais Schleiden (1838)

Studied plants with a microscope (said plants are mad up of cells)

Theodor Schwann (1839)

Observed different animal cells concluded animals were made up of cells

Rudolf Virchow

Hypothesized that cells divide to form new cells (summarized his ideas in the cell theory

Edward Jenner (1796)

made a smallpox vaccine by using sores of people who had cowpox, injected healthy people and they did not get smallpox.

zacharias janssen (1595)

a dutch lens maker that produced the first microscope