B3a- Molecules of Life

HideShow resource information
  • Created by: Alex
  • Created on: 18-04-14 13:53
What structures are in an animal cell and what do these do?
Nucleus-DNA (chromosomes), Cell membrane- controls what goes in and out, Ribosomes- protein synthesis, Cytoplasm- cell reactions, Mitochondria- respiration ( making energy)
1 of 29
Where are the most mitochondria found?
In cells which need a lot of energy: Liver cells- metabolic reactions, Muscle Cells- to contract
2 of 29
What other structures does a plant cell contain?
Chloroplasts- photosynthesis, Cell wall- made of cellulose: support, Vacuole- cell sap (weak solution of sugar and salts)
3 of 29
What is in a bacterial cell?
Cytoplasm, Cell membrane, Cell wall. Don't have a true nucleus (have a single circular strand- 1 chromosome of DNA that floats freely in cytoplasm), don't have chloroplasts or mitochondria.
4 of 29
Where are ribosomes found?
In the cytoplasm.
5 of 29
What are chromosomes and where are they found?
Found in the nucleus. Carry coded information in form of genes. Long molecules of coiled up DNA, divided up into regions called genes.
6 of 29
What type of cell structure is too small to see with a light microscope?
Ribsomes
7 of 29
What are genes and where are they found?
Made up of DNA. Make up the information for a specific characteristic. A section of DNA that codes for a particular protein and so has a different sequence of bases- what allows for unique proteins.
8 of 29
What is the structure of DNA?
2 strands coiled to form a double helix, each strand containing chemicals called bases (4 different types), with cross links between the strands formed by pairs of bases.
9 of 29
What does the double helix structure mean?
2 molecules stuck together by complementary base pairing (A,T,C,G). Can pull the 2 strands apart easily(unzip) so protein synthesis can occur. Double stranded spiral.
10 of 29
What are the two strands made up of?
Lots of small groups called nucleotides
11 of 29
What do nucleotides contain?
Small molecule called a base.
12 of 29
What are the complementary base pairs?
A to T and C to G
13 of 29
What keeps the two strands of DNA tightly wound together?
Cross links
14 of 29
What is the genetic code?
Information in the genes in the form of coded instructions. Control cell activity and therefore affects characteristics.
15 of 29
What controls the production of proteins?
DNA
16 of 29
What are proteins made up of and what are they used for?
Amino acids and growth and repair of cells.
17 of 29
How is the function of the protein worked out?
By the order of amino acids.
18 of 29
How is protein structure determined by DNA base code?
Triplet code determines amino acid sequence. 3 bases= 1 amino acid. Each protein has a different order of bases which gives the protein a different shape and therefore a different function.
19 of 29
What is the first stage of protein synthesis.
1- Transcription: mRNA copies the code from the DNA, so the code can be taken to ribosomes (DNA can't move out because its so big). mRNA acts as messenger between DNA and ribosome.
20 of 29
What is the second stage of protein synthesis?
2- Translation: transfers RNA molecules carrying amino acids. Matches their anticodon against their codons on mRNA. The amino acids link together as mRNA is "read" by ribosomes. This makes a protein. Folds to form complex shapes.
21 of 29
What is it that decides the order of amino acids in a protein?
Order of bases in the gene.
22 of 29
How are amino acids joined together to make proteins?
Following the order of bases in the gene.
23 of 29
What is the codon?
3 base sequence in DNA or mRNA which codes for an amino acid
24 of 29
What is the anticodon?
3 base sequence in tRNA (Transfer RNA) which matches against the codon in mRNA.
25 of 29
How does DNA control cell functions?
By controlling protein production. Proteins produced in a cell affects it's functions not the whole set of genes are used in a protein. Some genes are switched off which means the proteins they code for aren't produced. Genes: switched on=function
26 of 29
What did Watson and Crick do?
Worked out that DNA is shaped like a double helix
27 of 29
What data did they use from other scientists?
Franklin and Wilkins produced photo 51 with the use of X-ray crystallography to show shape. Chargaff discovered that there bases occurred in pairs.
28 of 29
Why is it important for other scientists to check the work?
To make sure the results are valid.
29 of 29

Other cards in this set

Card 2

Front

Where are the most mitochondria found?

Back

In cells which need a lot of energy: Liver cells- metabolic reactions, Muscle Cells- to contract

Card 3

Front

What other structures does a plant cell contain?

Back

Preview of the front of card 3

Card 4

Front

What is in a bacterial cell?

Back

Preview of the front of card 4

Card 5

Front

Where are ribosomes found?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all DNA and inheritance resources »