Class Notes (835,574)
Canada (509,252)
BIOA01H3 (687)


5 Pages
Unlock Document

Biological Sciences
Mark Fitzpatrick

Genetics DNA: Molecule found in Nucleus: Deoxyribonucleic Acid Structure: Double Helix, Twisted Ladder, Coiled in Chromosomes Function: To contain all of the instructions for life DNA inside chromosomes, inside the nuclei of the cell Structure: Deoxyribose: Sugar molecule Phosphate: w/ sugar makes backbone of ladder Nitrogenous Base: Adenine, Thymine, Cytosine, Guanine -Adenine + Thymine are purine: 2 rings -Guanine and Cytosine are purimidines: 1 ring Nucleotide: Phosphate + Deoxyribose + Nitrogenous base pair Base Pairs: Pairs of nitrogenous bases, always pairs AT and CG Gene: segment of DNA that encodes instructions for Protein RNA retrieves instructions from DNA and takes it out to make protein DNA twists on itself -> twists with Histone (beads) -> histones twist to make chromatid Chromosomes -Each human has 46 chromosomes -23 pairs in total -1 pair sex chromosomes (that define your sex, male XX, female XY) -22 pairs of autosomes (not sex chromosomes) -Each pair is homologous – same instructions but different messages -Not all living things have the same number of chromosomes Centromere: middle region of chromosome, attracts spindle fibers N: Haploid: # of unique chromosomes -> human is 23 2N: Diploid: # of total chromosomes Chromosome -> (before mitosis, copies in S phase) -> called “Sister Chromatids” when centromere is added Homologs: single chromosomes that are similar but not the same to another homolog Homologous Pairs: pairs of homologs after criss crossing that are ready for anaphase Cell Division Cell Division: Making new cells Mitosis: Occurs only in Somatic Cells -Daughter cell identical to parent cell Purpose: GROWTH, REPAIR, and REPLACE/REPRODUCTION Mitosis part of cell cycle Cell Cycle: 2 stages (Growth, and Division) growth being the longest Interphase: to increase volume and mass -G1: growth prepare to synthesize. Option to synthesize or rest phase -S (Synthesis) Phase: DNA duplication -G2 Phase: growth and prepare to divide. Chromosome made into 2 Sister chromatids held with centromere. Prophase: Chromatin condenses and becomes visible -Nuclear membrane breaks down -Begin to migrate to opposite poles, and held with spindle fibres Metaphase: Middle -Spindle Fibers attach chromosome and puts them on the equatorial plate -Sister chromatids face opposite poles Anaphase: Apart -Centromere splits -Sister chromatids pulled by spindle fibers Telophase: two -Nuclear membrane forms around each set of chromatids -Spindle fibers gone -Chromatids de condenses to chromatin. Chromatin = chromosome Cytokinesis: Occurs at the end. -cytoplasm divides into 2 through a pinching process -In plants, cell wall divides cell in half Meiosis: to mak
More Less

Related notes for BIOA01H3

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.