Lesson 4 Genetics Flashcards
Biomolecules made up of
Nucleotides
The genetic material of the cell
■ Double helical structure
DNA
DNA
Deoxyribonucleic acid
What does the DNA do?
Codes sequence of amino acids in proteins
■ Controls protein synthesis
IN OTHER WORDS…
■ It influences the trait and characteristic of an animal
What is the DNA composed of?
Sugar-phosphate backbone – Sugardeoxyribose
– Phosphate group
Nucleobase – Adenine
– Guanine – Cytosine – Thymine
■ Receives information from DNA
■ Carries the amino acids
RNA
RNA
Ribonucleic acid
What is the RNA composed of?
■ Sugar-phosphate backbone – Sugarribose
– Phosphate group
■ Nucleobase – Adenine
– Guanine – Cytosine – Uracil
What are the 3 main types of RNA?
■ Messenger RNA (mRNA)
– Receives genetic instructions for synthesizing proteins
■ Transfer RNA (tRNA)
– Picks up amino acids and helps
position the amino acids
■ Ribosomal RNA (rRNA)
– Along with proteins, makes up ribosomes
Receives genetic instructions for synthesizing proteins
■ Messenger RNA (mRNA)
Picks up amino acids and helps
position the amino acids
Transfer Rna (tRNA)
Along with proteins, makes up ribosomes
Ribosomal RNA
Creation of new DNA from one old template –
Semiconservative
Replication
Information from DNA to RNA
Transcription
Creation of protein
– Information from RNA to protein
Translation
SEXUALLY reproducing eukaryotes, have 2 types of body cells…
Somatic cells
Sex cells
What is cell division of gametes called?
Meiosis
A single germ cell divides into four unique daughter cells.
Meiosis
Daughter cells have half the # of chromosomes as parent cell,
so they considered
Haploid
one copy of each chromosome
– designated as “n”, the number of chromosomes in one “set”
- gametes
Haploid
two sets of chromosomes - two of each chromosome – designated as “2n”
- somatic cells
Diploid
organisms receive one of each type of chromosome from female parent (maternal chromosomes) and one of each type of chromosome from male parent
Diploid
Chromosomes exist in pairs in diploid (2n)
cells.
Homologous
Manysingle-celled organisms reproduce by splitting, budding.
Asexual reproduction
Some multicellular organisms can reproduce
asexually, produce
Clones
• Fusion of two gametes to produce a single zygote.
• Introduces greater genetic variation, allows genetic recombination.
• With exception of self- fertilizing organisms, zygote has gametes from two different parents.
Images: Peter, Lois & Stewie, The Family Guy
Sexual reproduction
In meiosis, there
are 2 divisions of the nucleus
Meiosis 1 and 2
Homologues break at identical locations, then rejoin opposite partners.
• This creates new combinations of the alleles on each chromosome.
• Occurs randomly several times on every chromosome.
• Results in mixing of the genes you inherited from your parents.
From the Virtual Cell Biology Classroom on Scien
Crossing over
Males produce sperm throughout life, after the onset of puberty, ab
1,500 sperm per second
During oogenesis, three develop as the mature ovum is generated.
Polar bodies
contain little cytoplasm and eventually degenerate.
Polar bodies
