lec 1- study of cell biology Flashcards
what is a cell?
The basic microscopic unit of all living beings, cells produce energy and use it to to build all the substances necessary for its life
what is an organ?
a fully differentiated structural and functional unit in an animal that is specialized for some particular function
what are tissues?
cells that aggregate to form a specific function
how were cells discovered?
they were discovered after the invention of the microscope in 1865 by Robert Hooke, named cells after the similarity to cells that monks in monastery’s lived in
State the cell theory:
- All organisms are composed of one or more cells
- The cell is the structural unit of life
- cells arise only by division from a pre-existing cell
do cells from different species share similar structure, composition, and metabolic features that have been conserved throughout evolution?
Yes
organisms are built according to what?
organisms are built according to information encoded in a collection of genes
why is the molecular structure of genes important?
the molecular structure of genes is important because it allows for changes in genetic information that lead to variation among individuals, which forms the basis of biological evolution
if all cells contain identical copies of DNA in an organism, what causes the DNA to differentiate?
development from a single fertilized egg
how do cells reproduce?
by division known as mitosis and meiosis
what happens to the cell before division?
DNA replication
how do animal cells derive energy?
Animal cells derive energy from the products of photosynthesis, convert glucose to ATP
what do all chemical changes that occur in a cell require?
enzymes
what does the sum total of chemical reactions in a cell represent?
the cells metabolism
how do vesicles move?
by travelling on microtubules with the help of motor proteins (kinesin)
how do cells respond to stimuli?
by the help of receptors
what are the methods of response a cell does to respond to stimuli?
altering metabolism, moving from one place to another, or even committing suicide
where did cells evolve from?
don’t know but all living organisms evolved from the last universal common ancestor LUCA
what are the similarities between eukaryotes and prokaryotes?
many common structural features, an identical genetic language, a common set of metabolic pathways
what are the model organism requirements, and what are the common ones?
relatively simple species, fast generation time, large number of offspring, easy to manipulate, inexpensive to breathing. mouse (mammal), fruit fly (insect), mustard plant (plant), zebra fish (fish), elegans (nematode), E. coli (bacterium), and saccharomyces (yeast)
what is the cell size limited to?
the volume of cytoplasm that can be supported by the genes, the volume of cytoplasm that can be supported by exchange of nutrients, by the distance substances can efficiently travel through cytoplasm via diffusion
what are the units cells are measured in?
nano or micro meters
what is a hypothesis?
a statement consistent with most data, must me testable
what is a theory?
a hypothesis that has been extensively tested , widely accepted
what is a law?
a statement of fact of a natural phenomena that has been tested and confirmed
