1.1 - Introduction to Cells Flashcards
Cell Theory
Cells are the smallest unit of life
All living things consist of cells
Cells arise from preexisting cells
Cell Standard Form
Discrete unit with specific parts and size
Atypical cells (as an exception to the standard form of the cell)
Striated muscle fibers
Giant algae
Aseptate fungal hyphae
Striated muscle fibers (as an exception to the standard form of the cell)
Larger than most cells, multiple nuclei
Giant algae (as an exception to the standard form of the cell)
Large unicellular organism, can grow up to 100mm despite having only one nucleus. An organism of this size would be expected to have more than one cell
Aseptate fungal hyphae (as an exception to the standard form of the cell)
Does not have cross walls or septa, and so forms a continuous cytoplasm, many nuclei
Functions of Life (MRHGREN)
Metabolism
Response
Homeostasis
Growth
Excretion
Reproduction
Nutrition
Metabolism
All enzyme-catalyzed reactions in a cell or organism
Response
Sensitivity to internal or external stimuli
Homeostasis
The regulation of a stable internal environment
Excretion
The removal of metabolic waste
Growth
Change in size or shape
Reproduction
Production of offspring, either sexually or asexually
Nutrition
Absorption or synthesis of organic materials to create energy
Paramecium
M: Reactions in the cytoplasm catalyzed by enzymes
R: Moves when touches solid object
H: Keeps internal conditions within limits
G: Increase in size and dry mass by accumulating organic matter
R: Asexual reproduction
E: CO2 diffuses out of cell
N: Ingests and digests smaller organisms
Cell Size
An increase in cell size leads to an increase in chemical reactions. This means more substances need to be taken in and removed. This depends on surface area and volume.
Reasons cells reproduce
Growth, reproduction and replacement
Emergent properties
The interaction of individual components creating new functions
Stem cells
Cells with the potential to develop into many different types of specialized cells in the body
Properties of Stem cells
Self Renewal (continuous division)
Potency (undifferentiated)
Stem Cell Collection
Embryonic or adult
Stargardt’s Disease
A genetic disease that can cause blindness in children. It causes photoreceptors to become degenerative. It is treated by injecting embryonic stem cells that can develop into retina cells into the back of the eyeball.
Magnification formula
M = I/A
