A homozygous organism with two recessive alleles Starter for 10 .... Place the statements in order ...... One card with 1 meaning Linked to a word on another DNA Reproductive (sex) cell that fuses with another of the same type of cell during fertilisation Gamete A homozygous organism with two recessive alleles

Higher Human Biology Unit 1 – Human Cells DNA

Learning Outcomes Content Explain the term genotype. Describe what the DNA molecule is made up from and how it is bonded. Process Model making! Benefit Understand how inheritance is carried out. Explain how CSI DNA works! P12 The genotype of a cell is determined by the sequence of bases in its DNA. DNA is the molecule of inheritance and can direct its own replication. Structure of a DNA nucleotide (deoxyribose sugar, phosphate and base). Nucleotides bond to form a sugar–phosphate backbone. Base pairs (adenine, thymine and guanine, cytosine,) held by weak hydrogen bonds forming a double helix. Double stranded antiparallel structure with deoxyribose and phosphate at 3' and 5' ends of each strand.

New Information The genotype (genetic makeup of an organism) of a cell is determined by the sequence of bases in its DNA. DNA is the molecule of inheritance and can direct its own replication. Made up of nucleotides.

DNA Nucleotide Structure of a DNA nucleotide (deoxyribose sugar, phosphate and base). O O=P-O Phosphate Group N Nitrogenous base (A, G, C, or T) CH2 O C1 C4 C3 C2 5 Sugar (deoxyribose) Pentose

DNA Nucleotide Structure of a DNA nucleotide (deoxyribose sugar, phosphate and base). O O=P-O Phosphate Group My house (sugar), a garage (base) and a satellite dish (phosphate group) N Nitrogenous base (A, G, C, or T) CH2 O C1 C4 C3 C2 5 Sugar (deoxyribose) Pentose

DNA Backbone Nucleotides bond to form a sugar–phosphate backbone. Base pairs (adenine, thymine and guanine, cytosine,) held by weak hydrogen bonds forming a double helix. Double stranded antiparallel structure with deoxyribose and phosphate at 3' and 5' ends of each strand.

Sugar-phosphate backbone Nucleotides bond to form a sugar–phosphate backbone. Covalently bonded (strong bond)at position 3 and 5 carbon.

DNA 4 Bases ..... 2 purines (double garage; double ringed structure) 2 pyrimidines (single garage; single ringed structure) Complementary base pairing due to hydrogen bonding A + T have 2 bonds C + G have 3 bonds ary

New Information The genotype of a cell is determined by the sequence of bases in its DNA. DNA is the molecule of inheritance and can direct its own replication. Structure of a DNA nucleotide (deoxyribose sugar, phosphate and base). Nucleotides bond to form a sugar–phosphate backbone. Base pairs (adenine, thymine and guanine, cytosine,) held by weak hydrogen bonds forming a double helix. Double stranded antiparallel structure with deoxyribose and phosphate at 3' and 5' ends of each strand.

DNA Double Helix P O 1 2 3 4 5 P O 1 2 3 4 5 G C T A

Activity Research one of these AMAZING scientists Make your own model of DNA! http://www.scienceinschool.org/2006/issue2/dna http://nobel.scas.bcit.ca/resource/dna/dna_sweets.htm http://www.yourgenome.org/landing_dgg.shtml http://www.geograph.org.uk/photo/2847164 - Newcastle http://www.tgac.ac.uk/spotted-dna-from-around-the-world/

Review Comment on each others DNA model; Positives comments Improvements that could be made