The cell Flashcards
Define the cell”
structural units of all living things
How many cells in human body/
50 to 100 trillion
4 concepts of cell theory
- A cell is the basic structural and functional unit of living organisms.
- The activity of an organism depends on the collective activities of its cells.
- According to the principle of complementarity, the biochemical activities of cells are dictated by the relative number of their specific subcellular structures (function is dependent on structure, and that the form of a structure relates to its function)
- Continuity of life has a cellular basis.
chemical components of cells
- carbon
- hydrogen
- oxygen
- nitrogen
Cells are about __% water
60
3 major region/ parts of a cell
- nucleus
- cytoplasm
- plasma membrane
What is the nucleus?
control center of the cell (contains deoxyribonucleic acid (DNA))
What is DNA needed for
building proteins and cell production
What is DNA needed for
building proteins and cell production
What are organelles?
specialized cellular compartments
many r membrane bound
compaertmentalization is critical for organelle’s ability to perform specialized function
Mitochondria function
powerhouse of cell
carry out reaction where oxygen is used to break down food
provides ATP for cellular energy
What does Mitochondria look like?
changes shape continuously
consists of a double membrane with cristae on the inner membrane
What are ribosomes?
made of protein and ribosomal RNA
sites of protein synthesis
found in cytoplasm and rough ER
What do ribosomes look like?
bi-lobed dark bodies
What is rough er?
studded with ribosomes
synthesizes proteins
transports vesicles more proteins within cells
abundant in cells that make and exports proteins
Smooth ER
functions in lipid metabolism
detoxification of drugs and pesticides
What IS endoplasmic reticulum?
Fluid-filled cisterns (tubules or canals) for carrying substances withing the cell
What is the golgi apparatus?
modifies and packages proteins arriving from the Rough ER via vesicles
produces different types of packages
What type of packages does the golgo apparatus produce?
SECRETORY VESICLES
LYSOSOMES
IN HOUSE PROTEINS AND LUPIDS
What does the golgi apparatus look like?
appears as a stack of flattened membrane associated with tiny vesicles
What are lysosomes?
membranous bags packages by the golgi apparatus
cotains enzymes produced by ribosomes to digest wornout or nonusable cellstructuers
hosts phagocytes that can duspose of bacteria and cell debris
3 types of surface extensions
cilia
flagella
microvilli
what is cilia
move materials across the cell surface - respiratory system to move mucus
flagella
propels the cell - sperm (only flagellated in humans)