Polvi's Part Flashcards
Who visualized cells first? When?
Hooke, around 1665
What did Hooke observe underneath a microscope? Were the cells dead or alive?
cork, the cells were dead
Why are cells called cells?
because under a microscope they looked like monks dorm cells
What are the first two principles of cell theory? Who proposed it?
That all organisms are composed of one or more cells
That the cell is the structural unit of life
Proposed by Schwann
Who proposed the third principle of cell theory, what is it?
Cells can only arise by division from a pre existing cell
What is the fourth principle of cell theory regarding genetic info?
Cells contain genetic information in the form of DNA, and that information is passed from parent to daughter cell
What are the basic properties of cells?
properties shared by all cells
List the basic properties of cells?
- Cells are complex and organized
- Cells contain genetic information (which is stored, used, and transmitted n the form of dna and rna
- Cells acquire and use energy
- Cells carry out an array of different chemical rxns
- Cells are involved in mechanical activities (not static, they transport materials, move the whole cell, move material within the cell)
- Cells respond to stimuli (via receptors)
- Cells self regulate (maintain homeostasis through an organized set of molecular tools)
- Cells evolve (all cells came from a common ancestral cell)
- Cells reproduce by division
What do all chemical reactions require to speed up the rxn time?
enzymes
Where is all the energy used by life derived from?
from the sun
What are hela cells?
These are cells derived from human cells and can keep dividing infinitely
What are hela cells named after?
Are cells that were taken from henrietta Lacks in the 1950’s without her consent while she was treated for cervical cancer
What did the case of Henrietta Lacks raise question about?
raised concerns about informed consent in biomedical research
Where are eukaryotic cells found?
Animals, fungi, plants, protists
What are prokaryotic cells found?
Bacteria
What the main difference between prokaryotes and eukaryotes?
Eukaryotes have membrane bound organelles, prokaryotes don’t
Do prokaryotes and eukaryotes differ in their plasma membranes construction?
no
Is the genetic code the same for DNA in eukaroytes and prokaryotes?
yes
What is in common between prokaryotes and eukaryotes?
- Mechanisms for transcription and translation of genetic info
- Similar ribosomes
- Same metabolic pathways
Similar apparatus for conservation of chemical energy as ATP - Similar mechanisms of photosynthesis
- Proteasomes of similar structure
- Cytoskeletal filaments built of proteins similar to actin and tublin
What are differentiating features between prokaryotes and eukaryotes?
- Division of cells into nucleus and cytoplasm
- Complex chromosomes
- Complex membranous cytoplasmic organelles
- Complex cytoskeletal system
What is a covalent bond?
A chemical bond in which electron shells are shared between two atoms- atoms are most stable when the outermost shell is full.
What are polar (hydrophillic) molecules?
Molecules with an uneven distribution of charge because the atoms in it have differing electronegativities
What are non polar (hydrophobic) molecules?
Molecules whose covalent bonds have a equal distributions of charge because the atoms in it have approx the same electronegativities
What are the features of polar uncharged amino acids?
composed of C’s and H’s majorly, but has uncharged O and N
What are the features of polar charged amino acids?
Have O’s and N’s w charges
What are features of nonpolar amino acids?
Has only H and C in side chain
What are the three type of noncovalent bonds?
A weak chemical bond based on attractive forces between oppositely charged regions
What is an ionic bond?
Is attraction between groups of opposite charges, interact w polar water so weak in it
What is an hydrogen bond?
interactions between H atom and second EN atom, involves a H bind donor, and acceptor
One is weak, many are strong ex: holds the double helix strand
What is an an der Waals interaction?
A weak attractive force due to assymetrical charges within adjacent atoms or mlcls. ex: antibody recognize antigens through this
What is the hydrophobic effect?
The tendency of nonpolar molecules to aggregate in order to minimize their interaction with polar water mlcls, is the basis for the formation of lipid bilayer membranes
