Decoding Info DNA-Origins Of life , FOR TEST Flashcards
1
Q
Name some fictions of proteins
A
- enzymes
- structural purposes
- determine the traits that we have
2
Q
Proteins are not ______ _______ from DNA.
A
Built directly
3
Q
RNA
A
Ribonucleic acid-nucleic acid made of nucleotides
4
Q
In what three ways does RNA differ from DNA?
A
- RNA consists of a single strand of nucleotides, not two strands
- RNA nucleotides contain the 5-carbon sugar ribose, not deoxyribose. Ribose contains one more oxygen than deoxyribose.
- RNA nucleotides contain A, G, and C like DNA, but instead of Thymine, RNA contains uracil, which is complementary to at adenine
5
Q
The instructions in DNA code for the _______________________________________.
A
Construction of proteins
6
Q
What’s Transcription and where does it take place?
A
The process by which a gene’s instructions for making proteins are transferred to an RNA molecule. Transcription occurs in the nucleus where the DNA is located.
7
Q
What is the first step in transcription?
A
RNA polymerase, an enzyme that binds complementary RNA nucleotides during transcription, binds to a special start sequence of DNA.
8
Q
What is the seconds step of transcription?
A
RNA polymerase unwinds and separates the two strands of the double helix.
9
Q
What is the third step in transcription?
A
RNA polymerase adds and links complementary RNA nucleotides as it reads the DNA.
(Transcription follows the base-pairing rules for DNA replication except that in RNA, uracil (instead of thymine) pairs with adenine)
10
Q
What is the fourth step in transcription?
A
Transcription proceeds until RNA polymerase reaches a stop sequence of bases that marks the end of a gene.
11
Q
What is the fifth step in transcription?
A
After transcription has completed, the two strands of DNA close up, reforming the double helix and the RNA strand separates from the DNA.
12
Q
Transcription is like DNA replication, only that ______________________________________.
A
One strand of RNA is produced instead of two strands of DNA.
13
Q
Also in DNA replication, both strands of DNA are used as templates, but in transcription, ________.
A
Only one strand is used.
14
Q
Different types of __________ can be formed by transcription.
A
Nucleotides
15
Q
Messenger RNA (mRNA) -At the \_\_\_\_\_\_\_\_\_\_\_, the instructions are "read" which code for \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_. Many \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ join together to make a protein. ~the RNA instructions are written as \_\_\_\_\_\_\_\_\_\_\_
A
Carries the instructions for building a protein from the DNA gene to the ribosome.
-Ribosomes, specific amino acids, amino acids.
~codons
16
Q
Codons
A
A series of three nitrogenous bases on the mRNA
17
Q
The Genetic code
A
Shows all 64 possible codons and the amino acids that they code for.
18
Q
What’s Translation? Where does it take place? What’s two types of RNA help this process?
A
Using different types of RNA molecules to read the instructions on mRNA and put together the amino acids that makeup the protein.
Takes place in the cytoplasm at the ribosomes.
tRNA and rRNA
19
Q
What’s tRNA
A
Transfer RNA:
Folded molecules that carry a specific amino acid on one end
Other end has an anticodon
20
Q
Anticodon
A
Three-base sequence that is complementary to an mRNA codon.
21
Q
What’s rRNA
A
Ribosomal RNA:
Helps make up ribosomes
Translation occurs at the ribosomes
22
Q
What’s the first step of translation?
A
mRNA leaves the nucleus and enters the cytoplasm. There, it attaches to a ribosome.
23
Q
What’s the second step in translation?
A
The ribosome “reads” the codon. A tRNA molecule with the complementary anticodon arrives and binds to the codon. The tRNA is also carrying its specific amino acid.
24
Q
What’s the third step in translation?
A
The tRNA molecule then separates from the amino acid, and leaves the ribosome.
25
What's the fourth step in translation?
The ribosome then moves along to the next codon and a new tRNA molecule takes its place on the mRNA strand. The new amino acid brought in joins the other ones (by forming a peptide bond)
26
What the fifth step in translation?
Amino acids are added to the growing chain, called a polypeptide chain until the ribosome reaches a stop codon.
27
What's the sixth step in translation?
The polypeptide chain is then let go, and it folds into a protein molecule.
28
Mutation
A change in the DNA of a gene.
29
Mutations can be passed on to offspring through the ______________________________
Gametes of an affected individual.
30
Mutations can occur in the body cells of an individual but these will only _____________________________.
Affect the individual in which they occur.
31
Gene rearrangements
| Example
Mutations that move an entire gene to a new location.
| Translocation
32
What's translocation?
The movement of part of a chromosome to a different location. Translocation may happen within the same chromosome or between different chromosomes.
33
Gene alterations
Mutations that change a gene itself
34
Substitution mutation and what it may result in.
A nucleotide with a different nitrogenous base replaces the original nucleotide.
Missense mutation, silent mutation
35
Missense mutation
Results in a change in a single amino acid in the inal polypeptide
36
Silent mutation
The new codon codes for the same amino acid so no change occurs.
37
Insertion
A piece of DNA is inserted into a gene.
38
Deletion
When a segment of a gene is lost
39
Insertion and deletions can change __________________. Example-imagine deleting the letter C from the sentence "THE CAT ATE". Keeping the "codons", or groups of three letters, the message would read ___________ which is meaningless. A mutation such as an insertion and deletion is called ______________________, since it causes a ________ to be read in the _____________________________.
The codon's groupings
"The Atate"
Frameshift mutation
Gene, wrong three base sequence
40
Evolution
The gradual change over time
41
What are the two types of evolution ?
Geological evolution and organic evolution
42
Geological evolution
Slow change of the earth over 4.5 billion years
43
Organic evolution
Change of species over time
44
Give an example of evidence of evolution
Fossils
45
Fossil
Trace or remains of an organism that has been preserved by natural process
46
Most fossils are found in ____________________ .
Sedimentary rock
47
Sedimentary rock
Forms on the bottoms of shallow seas of the ocean.
48
Oldest layers of sedimentary rock are on the ____________, youngest (most recent) are at ____________.
Bottom, the top
49
Many fossils came from species that are _______________________. When the last individual of a species has died, that species is said to be ______________.
No longer living today, extinct
50
Comparative anatomy
Study of structural similarities and differences among living things. The presence of certain types of similarities suggests evolutionary relationship between species.
51
Homologous structures
Parts of different organisms that have similar structures and development
52
Homologous structures are evidence that ______________________________.
Species evolved from a common ancestor.
53
Give four examples of homologous structures. And what purpose they serve?
Arm and hand of a human-adapted for grasping
Flipper of a whale-adapted for swimming
Limb of a dog-adapted for walking
Wings of bird and bat-adapted for flying
54
Analogous structures and an example
Structures that have similar external forms and functions but different internal structures
Ex-birds and insects both have wings, but they are different in structure and development
55
What are Vestigial structures?
In modern organisms the structures are _____________________________________________________.
In humans, vestigial structures include the _____________________________________________________.
Remnants from of structures that were functional in an ancestral form.
Reduced in size and serve little to no function.
Appendix, tailbone, and wisdom teeth.
56
What are the three types of similarities?
Anatomical similarities, embryological similarities, biochemical similarities.
57
Scientists can compare the embryological development of different species and determine _______________________________________.
- embryos of closely related species show ____________________________________________.
- -ex-
- --all have ________________________________.
- ---this supports the idea that all four had a _______
- ----the more closely related the species-the more they ________________________________________________.
Evolutionary relationships from them.
- similar patterns of development.
- -early development of fish, turtles, pigs, and humans
- --tails, gill slits, 2 chambered hearts
- ---common ancestor
- ----resemble each other during development
58
Biochemical similarities:
The closer the evolutionary relationship between two species, the more _________________________________.
Example-amino acids found in hemoglobin of closely related species are_________________________.
Alike their DNA and proteins will be.
| Ex-almost identical, DNA of human and monkey %98 the same
59
Jean Baptiste de Lamarck (1809)
Studied animals and believed that the variations with in a species were not constant. Rather, he believed that evolution In animals occurred based on their need to adapt to changes in the environment.
60
What two principles does Lamarck's theory rely on?
The law of use and disuse and the inheritance of acquired characteristics
61
What's The law of use and disuse? Is it true.
The more an animal uses a particular part of its body, the stronger and better developed that part gets. Also, the less the part is used, the weaker and less developed it gets.
True
62
What's the principle of the inheritance of aquifer characteristics? Is it true ?
Characteristics that an individual through use and disuse could be passed to its offspring.
Not true.
63
Give Example using Lamarck's theory of evolution and explain it.
Long neck Giraffes-
- ancestors had short necks and fed on grass
- food supply decreased, and giraffes had to stretch their necks to reach food higher up
- therefore their necks became longer
- this trait was passed on to their offspring
- over time, the giraffes neck became longer and longer
64
August Weismann _____________ _________'s theory of inheritance of acquired characteristics
Disproved, Lamarck's
65
How did August Weismann disprove Lamarck's theory?
- cut off the tails of mice for 22 generations
| - but in the next generation, the mice were always born with normal length tails
66
Charles ____________ traveled on a ship called __________ in 1831 and collected hundreds of specimens from around the world. He observed that there were _________________________________ as he traveled down the coast of South Africa. He visited the ___________________, and found many different species of ______________ living there. Each species was alike, yet ______________________________. He believed that all species originated from the mainland, but _____________ based on the __________________________________________.
Darwin, Beagle, gradual changes in each species, Galpagos Islands, finches, differed slightly from one another, evolved, different environments in each island
67
Darwin's theory is called _____________. There are _____ main points of his theory.
Natural selection, six
68
What are the six main points of Darwin's theory?
Overproduction, competition, variation, adaptations, natural selection, speciation
69
Darwin's theory: overproduction
Most species produce more offspring than are needed to maintain the population
70
Darwin's theory: competition
Living space and food are limited, so offspring must compete for survival
71
Darwin's theory: variation
Characteristics of individuals of a species may differ in certain traits. Some may be important, it hers may affect the individual's ability to get food, escape enemies, or find mates.
72
Darwin's theory: adaptations and what's considered an adaptation?
The individuals with the most favorable adaptations will have a greater chance of surviving and reproducing.
Any variation that improves an individual's chance of survival.
73
Darwin's theory: natural selection
Based on the environment, the individuals with the most favorable adaptations reproduce and pass these traits on to their offspring
74
Darwin's theory: speciation
Over many generations, favorable adaptations accumulate in the species and the unfavorable ones disappear. Eventually changes are so great that the result is a new species.
75
Giraffes according to Darwin:
Although most giraffes had ________ necks, ___________ existed among the population and _____________________________. When grass was scarce, these long-necked individuals ________ and ____________because they were able to ____________________________. Their offspring would therefore __________________________________________. As a result of ________________, the neck of the giraffes were slightly _________ in each ___________.
Short, variations, some long necked individuals existed, survived, reproduced, obtain more food, inherit the favorable trait of the long neck, natural selection, longer, generation
76
Rate of evolution: Gradualism
evolution occurs slowly and continuously over millions of years.
77
Gradualism is _______________'s theory
Darwin
78
The rate of evolution: Punctuated Equilibrium
A species stays the same for an extended period of time. Then, in a short period of time (a few hundred thousand years), there is a rapid evolution.
79
The fossil record supports Punctuated Equilibrium because there are________________________.
transitional fossils that are missing.
80
Observed natural selection: industrial melanism-explain the whole deal
See notes cuz too lazy to write it all out.
81
Bacterial resistance to antibiotics-explain the whole deal.
See notes cuz too lazy to write it all out.
82
Insect resistance to DDT-explain the whole deal.
See notes cuz too lazy to write it all out.
83
The origins of life: today scientists believe in ___________. However, where did the ____________________________________ ?
Biogenesis, first living things originate from
84
Biogenesis
Living things originate from other living organisms
85
Heterotroph hypothesis
Formulated by a group of scientists in the 1920s and 1930s, led by A.I. Oparin
Rest in notes.
86
Nowadays the air consists of...
Nitrogen (Na), oxygen (O2), carbon dioxide (CO2)
87
Primitive earth consisted of...
Hydrogen (H2), water vapor (H2O), ammonia (NH3), methane (CH4)
88
The temperatures were much _________ in primitive times
Hotter
89
What sources of energy were present in primitive times?
Radiation from radioactive elements
Electrical energy from lightning
UV light, visible light, and X-rays from the sun
90
What did Stanley Miller and Harold Urey's apparatus contain?
H2, H2O, NH3, CH4 and boiling water
91
Coacervates
Aggregates or clusters of large molecules
92
Coacervates were surrounded by a "shell" of water molecules that formed a ______________.
Bounding membrane
93
The earliest actual cells were...
Prokaryotic heterotrophic anaerobes
