Grade 10 - Genetics Flashcards
hozier is such a good singer ngl
Define DNA
like what is its purpose in life
DNA (deoxyribonucleic acid) is the genetic blueprints for every living being. It determines your attributes, e.g physical appearance, physiology, a little affect on personality
What are the 4 Nitrogen bases found in DNA?
Adenine, Thymine, Cytosine, Guanine
Each only bonds with one of the other bases
Adenine + Thymine, Cytosine + Guanine
Apples go under Trees, Cars go in the Garage
Where is DNA found in Eukaryotes?
Eukaryotes are organisms that have cells with a nucleus e.g animals, plants
In Eukaryotes, the DNA is found largely in the Nucleus, but also the mitochondria, and in the case of plants, chloroplasts.
Where is DNA found in Prokaryotes?
Prokaryotes are organisms that have cells without a nucleus e.g bacteria
In Prokaryotes, the DNA is found in the Cytoplasm
What is DNA made of?
DNA consists of many smaller building blocks - nucleotides - that are each composed of a Sugar (Deoxyribose), Phosphate and a Nitrogen Base.This is all built in a double helix form. DNA is also anti-parallel, meaning one side is upside down.
you can search up simple nucleotide structure to see what it looks like
How does DNA determine the attributes of an organism?
DNA determines the attributes through the sequence of the nitrogen bases, with the only difference between organisms and species being the sequence of the DNA
How does DNA replication happen?
DNA replication first starts with a section of the DNA splitting in 2. Then, each side is copied and pasted1, and the newly formed copy bonds with the old copy, forming 2 new strands of DNA. Each strand has one half of the original, and one half new copy
1 Not really, an enzyme just brings in nucleotides with the corresponding nitrogen base to the ones that are attached to the original strand
What is the enzyme that splits the DNA in replication called?
The enzyme Helicase “unzips” the DNA
What is the enzyme that brings in the nucleotides called?
The enzyme “polymerase” brings in nucleotides to form the new DNA section
When does DNA Replication occur?
During the S-Phase of interphase in the cell cycle
Define Gene
Genes are sections of DNA that are code for a specific heritable characteristic
Define Allele
An allele is a specific form of a gene (such as dominant or recessive), differing from other alleles in the same gene by a few nitrogen bases, while also occupying the same locus (location)
Basically, the different options that a gene could be, e.g blonde hair is one allele, and brown hair is another allele, with hair color being the gene
Define Genome
All of the genetic information of an organism
Define gene pool
All of the genes possible in a population
Define gene mutation
A gene mutation is a random change in DNA, which usually occur when cells are making copies of DNA for cell division. It can only be passed on to offspring if the mutation occurs within sex cells
Define karyotype
A photograph of chromosome pairs
What are chromosomes made of?
Chromosomes are proteins which are wrapped in DNA
What is RNA and how is it different from DNA
RNA (ribonucleic acid) is a nucleic acid, like DNA. However, it only has one strand instead of 2, the nitrogen base thymine is replaced with uracil, meaning that A bonds with U instead of T, and the sugar is ribose instead of deoxyribose
What are the 3 versions of RNA
mRNA - Messenger RNA
rRNA - Ribosomal RNA
tRNA - Transfer RNA
What is the function of mRNA?
mRNA copies the sequence of the nitrogen bases, or the code, from the DNA in the Nucleus and carries it to the ribosomes. 3 consecutive nitrogen bases on an mRNA strand is called a codon
What is the function of rRNA?
It makes up the ribosome (surprise surprise), and it is located in the cytoplasm and on the rough ER (its an organelle in the cell, we learned about it last year but i dont think we need to know anything about it)
What is the function of tRNA?
The tRNA travels to the ribosomes to transfer amino acids. It knows what amino acids to bring by having a matching anticodon to each codon in the mRNA. You can find out what amino acid matches to what codon by checking the codon chart, the circle thingy we used in class
What is the purpose of all 3 RNAs?
To make proteins, which is necessary to carry out all metabolic functions. Proteins are made up of amino acids.
What are the 2 steps in protein synthesis?
Protein Synthesis = Making proteins
- Transcription - Making RNA
- mRNA is made by copying the nitrogen base sequence from DNA in the nucleus, where it then leaves the nucleus to the cytoplasm - Translation - Making proteins
- tRNA copies the codons from the mRNA, and transfers the matching amino acids to the ribosomes, where they are assembled into proteins
The slides have some great images showing this
How are Proteins synthesized?
- Amino acids are assembled in a specific sequence, according to the information from the mRNA
- There are 20 amino acids, and 64 codons, meaning some amino acids have more than 1 codon
- All protein synthesis begins with a start codon, which is AUG. The amino acid for this codon is methionine
- There are multiple stop codons, including UAA, UAG & UGA
- The stop codons just tell the ribosome that the protein is done and can be released
What is Mendelian Genetics?
Mendelian Genetics is the conclusion gathered by Gregor Mendel. These include:
1. Heredity consists of various factors, now called genes, that are passed from parent to child
2. Both parents contribute 2 copies of a gene each, but only one of the is inherited, and the one chosen is random 1
3. Some alleles are dominant, and some are recessive. The dominant prevent the recessive from being expressed in the organism
1 Each parent gives 2 genes because they also had 2 parents
Define dominant and recessive alleles
Dominant Alleles are represented through a capital letter, and while always be expressed if they are present in the gene
Recessive Alleles are represented through a lowercase letter and will only be expressed if there are no dominant genes
Define homozygous and heterozygous
in terms of alleles
Homozygous, or purebred, means the organism inherited the same allele from each parent (TT or tt)
Heterozygous, or hybrid, means that the organism inherited one dominant and one recessive gene (Tt)
i cant come up with a gay joke for this im sorry
Define genotype and phenotype
Genotype is the genetic makeup of an organism, being represented with letters (TT, Tt or tt)
Phenotype is the genotype when it physically expressed, e.g tall or short, green or yellow blablabla
What are Punett Squares?
Punett squares are methods of determining the possible genotypes of an offspring of 2 organisms.
The columns represent one parents allele, and the rows the other’s. Where the individual letters intersect, they combine to show one possibility for the offspring’s allele.
Each individual box has the same 1 in 4 chance of being the allele of the offspring, however multiple boxes in a punett square can have the same allele.
I cant really help yall revise these youll just have to look at the worksheets we did or something
