Lecture 8: Basic Cell Biology Flashcards
3 tenets of Cell Theory
- cells are the most basic functional units of life that can do all the functions of life
- all organisms are composed of cells
- all cells come from pre-existing cells
what are the functions of life?
- reproduction
- metabolism
- growth
- response
- homeostasis
what function of life is demonstrated by the contractile vacuoles in a paramecium?
homeostasis
cell division in bacteria?
binary fission
what fundamental statement of cell theory explains mitosis?
3. all cells come from pre-existing cells
common features of ALL cells
- cell membrane: surrounds the cell
- genetic material: DNA and RNA
- Ribosomes: site of peptide synthesis
- metabolism
What is required for life to evolve?
- formation of small molecules that contain carbon and hydrogen
- formation of self-replicating information-containing molecules
- development of membrane
molecules found on early Earth
- no free oxygen present
- water vapor
- Hydrogen gas
- methane
- ammonia
- hydrogen sulfide
- carbon dioxide
3 domains of life
- bacteria
- archaea
- eukaryotes
Which of the domains of life are prokaryotes?
bacteria and archaea
The first cells were….
- heterotrophic prokaryotes: consumed other molecules to get energy
- only life for 2 billion years
- origins of modern day photosynthesis and respiration
What is false about the amount of O2 present in the atmosphere since Early Earth
O2 is stable now
cyanobacteria
current day photosynthetic prokaryotes
do photosynthetic prokaryotes have chloroplasts?
no, prokaryotes do not have membrane-bound organelles; but, they do produce photosynthetically
plants have ____ and ____
mitochon and chloroplasts
all eukaryotes have
mitochondria
what happens to the value of the ratio as the numerator becomes larger relative to the denominator?
the ratio gets bigger
what determines the size of the cell?
the ratio of the surface area to the volume
volume formula
L x W x H
surface area
L x W (for all sides)
differences between prokaryotes and eukaryotes
- prokaryotes have a single, circular chromosome. eukaryotes have multiple double helix chromosomes that are coiled around proteins
- eukaryotes have membrane bound organelles; prokaryotes don’t
chromatin vs chromosomes
chromatin = DNA + histone proteins; but it is unraveled DNA for replication and transcription
chromosomes = DNA + histone proteins; discrete linear molecules of DNA for hereditary
Differential gene expression
cells in multicellular organisms differentiate to carry out specialized functions by expressing some of their genes but not others
