Class Notes (808,386)
Canada (493,174)
York University (33,530)
Natural Science (2,766)
NATS 1675 (233)
all (7)

(3) Chapter 18- Cell Division.docx

5 Pages
Unlock Document

York University
Natural Science
NATS 1675

Chapter 18 Cell DivisionJANUARY 29TH 2014There are two types of cell division mitosismeiosis MITOSISa kind of cell division in which two identical cells are producedIt is used as one method of reproduction for single celled microorganisms such as protests and bacteriaIt is also the type of cell division that occurs in multicellular organisms for growth repair and replacement We want the exact same cell carrying the exact same information People start out as one cell and from that point on it is mitosis When you reach your adult height this division is not longer needed for growth but it still good for repairreplacementMEIOSISa process of cell division by which gametes containing half the normal number of chromosomes are producedMeiosis is also called reduction divisionThis division is going on through your reproductive organs We have 23 pairs or 46 chromosomes 23 from mom 23 from dad You want your off spring to have the same number of chromosomes GAMETESsex cells eg egg cells sperm cells pollen grains A unisex term for a cell that have undergone meiosis CHROMOSOMEa strand of DNA and protein found in the nucleus of a cell carries genetic informationIn humans there are 46 chromosomes or 23 pairsWhen the chromosomes are spread out and thin they are chromatinDNAdeoxyribonucleic acid the chemical molecule that makes up chromosomes and genesDNA carries the code to make you humaneveryone has the same copy while other genes carry the distinctive GENEfunctional unit of heredity the part of the chromosome that transmits a particular hereditary traitA gene can be likened to a set of blueprints Ex intelligence height hair TRAITgenetic characteristicIf I had a string of pearls that was clipped together like a necklace A string of beads would represent a chromosome Each bead would represent a gene and each gene is coating for a specific trait ex skin colour tongue curlingHOMOLOGOUS CHROMOSOMESa pair of chromosomes 1 from mom1 from dad that carry genetic information for the same traits eg eye colour hair colour etcThey are look alikes If you are staining them they are the same colour Fig 181 shows a stained karyotype All genes from 122 are the same and you cannot tell which one is from male or female The difference between the man and women is one gene on the chromosomeKaryotype Karyo kernals DIPLOIDhaving the normal paired homologous chromosomes of somatic cells also referred to as 2N Fruit flies have 8 chromosomes D DoubleAre body cells SOMATIC CELLSbody cells Any cells in your body except for egg or sperm cells
More Less

Related notes for NATS 1675

Log In


Don't have an account?

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.