Alberts Chapter 1 Flashcards
What is the basic living Input – output of all living things
They take raw materials from their surroundings ,and use it to make copies of themselves
What is the most basic knowledge about commonality of living things
They are all made of cells – small membrane enclosed units filled with Aquatic solution of chemical that are able create copies of themselves by growing and divide into two
what is the main counterpoint of biology
the variety of individuals Vs the consistency of fundamental mechanisms
what enables us to study all forms of life
the fact that the specification of all living organisms is written in common molecular code
What differentiates living organisms from other process?
The phenomenon of heredity That the parent hands to its offspring detailed specifications of the characteristics the offspring will have it specifies a complex system of chemical processes
how many cells are in the human body (approximately)
10^13
What is the basic general characteristic of a single cell
- contains all the information that defines a specie 2.contains mechanism to gather raw materials from the environment and Construct with them a new copy of itself with that will have same information.
Explain how a computer and a cell are alike
Computer gave us the concept of quantifiable information encoded as 0 and 1 Cells are units of information that is encoded in DNA in 4 monomers , the nucleotides A,T,C,G.
Specify the X universal features of cells on earth (to be updated)
- All cells contain hereditary infromation in the same linear chemical code : DNA
- All cells replicate their hereditary information using templated polymerization
- All Cells Transcribe Portions of Their Hereditary Information into the Same Intermediary Form: RNA
What are nucleotides made of
Nucleotides are made of a deoxyribose sugar-phosphate molecule attached to a nitrogen containing base The bases are of four types -adenine, guanine, cytosine, and thymine. corresponding to four distinct nucleotides, labeled A, G, C, and T.
what are the qualities that give DNA strand its polsrity and what it serves
the individual sugar-phosphate unit have an asymmetric shape ,giving the backbone of the strand a definite directionality, or polarity: The 5’ end (linked to phosphate) and the 3’ end (free Hydroxyl) guides the process of copying and interpterion of information in the cell , the information is always “read” in a certain order (like English from left to right)
3’ attach to the 5’ in the antiparallel
what is the templated polymerization of the nucleotides (DNA replication)
- DNA is not created as an isolated strand it is Synthetized from a preexisting DNA strand (a double strand that splits serving as two tepmlates with the nitorgen bases sticking out
- Complementary Base Pairing : the rule defined by the complmentary (like lock and key) molecular sturctures of the bases-> G only to C (3 H bonds) A only to T (2 H bonds)
- this control what new monomere should be added as the “fresh” monomers are held by this base pairing (the new one is according to the next basis that sticks out)
- the two twist around each other (half of the old , and the new) creating 2 new copies of the original with the same hereditary information
What are the types of bonds in a the double helix
- The sugras connects to a next nucleotide’s phosphate group in a covalent bond
- The complementary connection between the bases has a hydrogen bonds
those type of bonds allow the strands to twist without breaking the “backbone”
What are ionic and covalent bonds
- They are all functions of electronegativity (the ability to attract electrons ) difference between two atoms. 2. Ionic bonds – strongest bond between atoms with ElcNeg diff >2.0 (electrons stolen not shared) 3. Covalent bonds a. Polar = ElNeg diff < 1.7 and > 0.5 electron is biased toward more EG atom b. Non polar Elneg < 0.5 electrons are shared equally
what Are hydrogen bonds
when there is a molecule where the electrons of a hydrogen atom are bonded stronger
electronegative atom like H2O, the hydrogen side ( the end further from the strong nucleus)
will attract and bond the positive side (O end) of another molecule
what are polymerization and condensation
polymerization is a process where two or more molecules link together it is done by:
condensation is a type of polymerization that produces water as by products :
- two monomers with OH (hydroxyl group) on their ends
- an hydroxyl group is removed from one monomer and an oxygen atom from the other
- the one free oxygen allows the monomers to bind together
- the by product produced in 2 is water , the by product.
“How does a polymer chain created by condensation “breaks””
Via hydrolysis reaction – an addition of water molecule breaks the bonds that holds the monomers
together .
what is are the gnereal differences between branched and unbranched polymers
unbranched polymers
- Have a linear structure
- Are tight and dense
- Have high melting points
Branched polymers
- Have branches (not a single line)
- Are loose and not dense
- Have lower melting points
What is DNA and how what is its basic construction (basic)
he double helix DNA (Dexoyrebonucleic-acid) is the form in which cells stores the hereditary information.
it Is a
- double stranded molecule
- a long unbranched, paired polymer chain
- the polymers are constructed from 4 types of monomers the nucleotides
- each noculeotide is made of sugar-phosphate and a nitrogen containing base of A,C,T,G
- Nucleotides are strung together in a linear sequence (each sugar connects to the next via the phosphate)
- that sequence encode the hereditary Information.
what are the 2 groups of nitrogenous bases
Purines = Double ring bases
Adenine and guanine
pyrimidines =Single ring basis
Cytosine and thymine that
In what 2 ways transcription is different from replication
1.The same DNA segment can be used as template for many RNA molecules (they depart from it
after formation )
2.many different RNA molecules can be made from a single strand by transcribing different
segments of it
What is the “expressive” role of DNA and what are the two steps in it
Guiding the synthesis of other molecules inside the cell mainly Proteins And RNA
It is done by
- Transcription – templated polymerization using segments of the DNA as templates for synthesis of the shorter polymer RNA (closely related to DNA ,representing part of the hereditary information) that is used to guide step 2
- Translation – guided by RNA molecules (in their intermidary role as mRNA , proteins are synthesized according to the Hereditary information from the DNA
What are the main structural differences between DNA and RNA
The sugars in RNA are Ribose unlike DNA deoxyribose and instead of thymine it has uracil (still binding to same DNA bases U binds to A )
