330 likes | 352 Views
Interim 2 review. Meiosis- forming sex cells. Process in which haploid cells are formed from diploid cells In humans: Parent 46 46 Parent Diploid (2N) Diploid (2N) Ovum 23 23 Sperm Haploid (N) Haploid (N) Zygote 46
E N D
Meiosis- forming sex cells • Process in which haploid cells are formed from diploid cells • In humans: Parent 46 46 Parent Diploid (2N) Diploid (2N) Ovum 23 23 Sperm Haploid (N) Haploid (N) Zygote 46 Diploid (2N) Chromosome number cut in half Fertilization
Meiosis Meiosis I Meiosis II
Meiosis • During meiosis I, the ______________________ chromosomes separate. • What does this do to the chromosome number? • During meiosis II, the sister ____________________ separate. homologous Cut in ½ chromatids
Meiosis II Prophase II Metaphase II Anaphase & Telophase II
Meiosis in Males and Females • Males- results in 4 sperm cells • Females- results in one ovum (egg) and 3 polar bodies MALES FEMALES 1st cell division 2nd cell division 4 Sperm cells 3 polar bodies 1 ovum
If three cells undergo meiosis in males, how many sperm cells will be produced? _____________ • If four cells undergo meiosis in females, how many ova (eggs) will be produced? _____________ • How many polar bodies would be produced for the same 4 cells? __________________ 12 4 12
16 • If the 2N number of an organism is 32; • how many chromosomes are found in a sperm cell? _______ • how many chromosomes are found in a diploid cell? _______ • how many chromosomes are found in an ovum? _______ • how many chromosomes are found in a haploid cell? _______ • how many chromosomes are found in a skin cell?________ 32 16 16 32
. variation • Sexual reproduction is important to the survival of the species because it adds genetic _________________________ to the population.
Genetic variation • Crossing Over- exchange of genetic information by non- sister chromatids during meiosis.
Mistakes in the Meiosis Nondisjunction- failure of chromosomes to separate properly
Genetics Vocabulary • ________________- the passing of traits from parents to offspring • ________________- the study of heredity • _________________- rod-shaped structures in the nucleus that transmits genetic information • _________________- units of hereditary information found on the chromosomes heredity genetics chromosomes genes
Genetics Vocabulary dominant • __________________- a gene that masks the expression of another gene in a pair ( Symbol- capital letter) • __________________- a gene in a pair that is hidden by the dominant gene (Symbol- lower case letter) • ___________________- two genes in a pair that are identical. (RR or rr) • _____________________- individual with one dominant and one recessive gene in a pair. (Rr) recessive homozygous heterozygous
Genetics Vocabulary • ______________________- either member of a pair of genes that determines a single trait. • ____________________- the pair of alleles represented by the capital and lower case letters. • ______________________- the trait that is actually expressed in an organism allele genotype phenotype
Immunity to poison ivy is a dominant trait while those people who get poison ivy show the recessive trait. Diagram a Punnett Square for a man who is heterozygous and a woman who get poison ivy. I i 1. What is the man’s genotype? ___________ 2. What is the woman’s genotype? ____________ 3. What is the probability of producing a child who gets poison ivy? __________ 4. What is the genotypic ratio?___________ Ii i i Ii ii ii 50% Ii ii 1:1
Feather color in birds is an incomplete dominant trait. Genes for blue feathers and genes for white feathers combine to form birds with silver feathers. Diagram a cross for two silver feathered birds. B W 1. What is the parent’s genotype? ___________ 2. What is the phenotypic ratio? ____________ 3. What is the probability of producing bird with blue feathers? __________ 4. What is the probability of producing a bird with silver feathers?___________ BW B W BB BW 1:2:1 25% BW WW 50%
1. What are the genotypes in the offspring? ___________________ 2. What is the genotypic ratio? ____________ 3. What is the phenotypic ratio? __________ 4. What is the probability of producing a child with blood type A? _______ 5. What is the probability of producing a child with blood type O? ______ • Blood type is a codominant trait. A man with blood type AO marries a female with blood type AB. AA, AO, AB, BO A O 1:1:1:1 2:1:1 A B AA AO 50% AB BO 0
Eye color in canaries is a sex-linked trait. Black eyes are dominant and red eyes are recessive. A red-eyed female is crossed with a black-eyed male. • What is the male’s • genotype? __________ • 2. What is the female’s genotype? _________ • What is the probability of producing a • 3. black-eyed female? _______ • 4. black –eyed male? _______ • 5. red-eyed female? ________ • 6. red-eyed male? __________ XBY Xb Xb Xb Xb XB Y XBXb XBXb 50% 0 XbY XbY 0 50%
Label the three parts of the nucleotide below. phosphate • ______________ • B.______________ • C.______________ sugar base
Adenine Thymine In DNA, how do the bases bond? _____________ bonds with ____________ and _____________ bonds with ____________ Cytosine Guanine
What is the name of the process in which DNA makes an exact copy of itself? __________________________ Replication
Put the steps of DNA replication below in order. • 1. Free floating nucleotides attach to complementary bases on both sides • 2. Sugars and phosphates join together on the new strands • 3. DNA molecule unzips • 4. Two DNA molecules are produced each made of one new strand and one template ________→ ________→ ________→ ________ 3 1 2 4
Comparison of DNA and RNA 2 1 deoxyribose ribose A with T C with G A with U C with G Nucleus to cytoplasm nucleus
Transcription • Protein Synthesis is divided into two processes. • Process 1- _____________________________-mRNA is made by copying the code from a DNA molecule. This process occurs in the __________. • Process 2-_____________________________- a protein is assembled from amino acids. • This process occurs in the _______________ at a _____________________. nucleus Translation cytoplasm ribosome
Genetic information usually follows in one specific direction (Central dogma of biology). Which of the following BEST represents this flow? • A.) DNA-->Protein-->RNA • B.) Protein-->RNA-->DNA • C.) RNA-->Protein-->DNA • D.) DNA-->RNA-->Protein
Three bases on the mRNA molecule that code for one amino acid is a(n) • A.) anti-codon. • B.) codon. • C.) tRNA. • D.) protein.
Transcribe the section of DNA below. G A C T T A C A G C U G A A U G U C
5 • Label parts 1 through 5 in the diagram. • 1. _______________ 4. _______________ • 2. _______________ 5. _______________ • 3. _______________ 4 1 3 2 tRNA Amino acid mRNA Protein ribosome
5 What is the name of the process in the picture? _____________________ 4 1 3 2 Translation
Mutation • A mistake in the genetic code is called a ____________________. • Name the type of mutation in the DNA sequences below. Use these choices Substitution Insertion Deletion • Original strand – CTGACT • New strand CTAGACT ___________________ • New strand CTGCT ___________________ • New strand CTGAGT ___________________ Insertion Deletion Substitution
Gel Electrophoresis • ___________ ____________________ is a method used to separate and analyze DNA fragments. • __________ ____________________ is the analysis of DNA fragments to identify an individual. DNA fingerprinting cs s2 s3 s5 s1 s4 CS= crime scene DNA s1= suspect 1 s2= suspect 2 s3= suspect 3 s4= suspect 4 s5= suspect 5