A&P 1 Chapter 4 Genetics and Cellular Function
What sugar is in DNA? RNA?
DNA: deoxyribose RNA: ribose
DNA
Deoxyribonucleic acid-
which as paired based and which does not? DNA or RNA?
Dna is paired and RNA is not
where there is a C on the DNA backbone there is usually a
G
DNA carries
Genetic code/information for making a particular protein
chromosome territory
Permeated with channels that allow regulatory chemicals to have access to the genes
kinetochore
Protein plaque on each side of the centrome.A structure of proteins attached to the centromere that links each sister chromatid to the mitotic spindle.
What are adenine and guanine classified as and are they single or double carbon nitrogen rings?
Purines double
what is a known as a disposable molecule that works mainly in the cytoplasm?
RNA
where there is an A on one backbone there is usually a
T
what do the proteins in dna form
a fine filamentous material called chromatin
across from a purine on one backbone, there is
a pyrimide bond
Chromosomes
a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.
gene
a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.
name the double ringed purines
adenine and guanine
What 2 bases in DNA form 2 hydrogen bonds with each other
adenine and thymine (think of the word AT)
What nitrogeneous bases do RNA contain?
adenine, guanine, cytosine, uracil
what are the sidepieces of the DNA helix called?
backbone
which component varies from one nucleotide to another in DNA?
bases
What kind of apprearance do chromatin have
beads on a string
what is the function of RNA
carries out and stores the instruction/information from DNA that is essential for the assembling/manufacturing of proteins; they can act as enzymes.
what is the essential function of DNA?
carry instructions called genes for the synthesis of proteins
what is the function fo DNA
codes for synthesis of RNA and protein
Each nucleosome consists of
core particle
what does each nucleosome consist of?
core particle and a short segement of linder DNA leading to the next particle
where does the RNA function?
cytoplasm
What are the 4 bases in DNA
cytosine (C) thymine (T) Adenine (A) guanine (G)
what does mRNA, rRNA and tRNA have in common with DNA? And how do they differ?
difference is RNA is smaller DNA is a double helix and RNA is only one nucleotide chain, not held together by base pairs sugar in RNA is ribose and in DNA it is Deoxyribose
Number of nitrogeneous bases in DNA and RNA
dna averages 10(8) base pairs rna 70-10,000 bases, mostly unpaired
what is the structure of dna described as?
double helix (twisted ladder)
histones
each bead of a chromatin 8 protein molecules around which DNA is tightly coiled in chromatin
the static structure of the dna state can change
from moment to moment according to the genetic activity of the cell as individual genes are turned off and on
where is the site of action for DNA?
functions in the nucleus and cannot leave
chromatin
granular material visible within the nucleus; consists of DNA tightly coiled around proteins
what 2 bases in DNA form 3 hydrogen bonds with each other
guanine and cytosine
What do bases do in DNA helix
hold the 2 backbones together with hydrogen bonds
how are the nucelosomes arranged
in a zig zag pattern, folding the chromatin like an accordian
where is the genetic code contained
in the four bases of DNA
where are the nucleosomes located
in the nucleos
what happens when a cell is preparing to divide?
it makes an exact copy of its nuclear DNA
where is the site of action for RNA?
leaves the nucleus functions mainly in the cytoplasm
Forms (principals) of RNA in a cell that produce proteins
messenger RNA (mRNA) ribosomal RNA (rRNA) transfer RNA (tRNA)
Nucleotide is one of the ___________of DNA and RNA
monomers
Is DNA replaceable?
no
can a given purine arbitrarily bind to just any pyrmide
no
can you see chromatin in a nonliving cell with a scope
no
what are the orders of structure that make the chromosomes more compact
nucleosome arranged in a zig zag pattern folding the chromatin like an accordian the strand is thrown into complex, irregular loops and coils that make the chrom thicker each chrom is packed into its own spherial regin of the nucleus called chromosome territory
organic molecle made up of a sugar, phospate group and nitrogen base
nucleotide
Where does the DNA function?
nucleus
Where are chromosomes found?
nucleus of a cell
the ________ of each small, single ringed _______with a large double ringed _______ gives the DNA molecule its form
pairing pyrimide purine
What are the steplike connections between the backbones of DNA
pairs of nitrogenous bases
what is the backbone (sides of the helix DNA) composed of?
phosphate groups alternating with the sugar deoxyribose
DNA and other nulceic acids are
polymers of nucleotides
what is on each side of the centromere
protein plaque called kinetochore
Are there more proteins or genes in the body
proteins
What is DNA complexed with?
proteins
______ are large double ringed bases
purine
what are the 2 classes of bases for DNA and explain them?
purine Adenine and guanine pyrmidines cytosine and thymine
_____are small single ringed bases
pyrimide
what are cytosine and thymine classified as and are they single or double carbon nitrogen rings?
pyrimidines single
nucleosome
repeating subunit of chromatin fibers, consisting of DNA coiled around histones
RNA
ribonucleic acid; a nucleic acid that plays an important role in the production of proteins
what is the sugar found in RNA
ribose
Gene
sequence of DNA that codes for a protein and thus determines a trait
What are the basic compounds of dna
sugar phosphate groups organic rings (nitrogeneous bases)
what is deoxyribose?
sugar found in DNA
What does a nucleotide consist of?
sugar, phosphate group, nitrogen basen(single or double hinged)
What are the 3 components of a nucleotide?
sugar, phosphate, nitrogenous base
law of complementary base pairing
the fact that one strand governs the base sequence of the other
what does dNA need to produce protein?
the help of mRNA, rRNA and tRNA
which way do the bases face in the helix
the inside
Centomere
the region of the chromosome that holds the two sister chromatids together during mitosis
what is a core particle?
the spool of histones with the dna ribbon around them
what happens to chromosomes when they replicate in cell division
they double
DNA is a
threadlike molecule with a uniform diameter of 2nm.
why do cells move to different territories
to allow genes on different chromosomes to partner with each other in bringing about developmental changes in the cell
WHat is DNA known for
to be the repository of our genes
what is the essential function of three principal RNA"s?
to interpret the code in DNA and use those instructions to synthesis proteins.
where do whole chromosomes migrate to when a cell develops
to new territories
dna does not exist as a naked double helix in the nucleous of a cell
true
what makes the chromosome thread thicker
winding the dna around the histones
What do chromosomes consist of?
2 genetically idential sister chromaids
each chromosomes consists of
2 identical parellal filaments called sister chromatids
How manu genes are humans estimated to have
20,000
how many molecules of DNA do most human cells have
46
what does chromatin occur as
46 long filaments called chromosomes
how many protens are on a bead of chromatin?
8
how many times does a chromatin thread repeat itself
800,000
what are base pairs
A-T G-C
What are the nitrogenous bases in DNA?
Adenine, Thymine, Cytosine, Guanine
What is Nucein?
An acidic phosphorus acid rich substance
nucleosomes
Bead-like structures formed by histones and DNA
what governs the patterns of base pairing in DNA?
C and g pair A and t pair
What happens in prophase?
Chromosomes condense Nuclear membrane disintegrates Centrioles move to opposite poles Spindle apparatus formed by microtubules
Name the single-ringed pyrimidines and their pairings
Cytosine and Thymine
who is known as giving orders?
DNA
What are the types of nitrogeneous bases in dna and rna
DNA A T G C RNA A U C G
what is the difference between DNA and chromatin?
DNA is the blueprint of life. Chromatin is the uncoiled DNA
