Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Genetics quiz
| Term | Definition |
|---|---|
| why do cells divide | For growth, repair and reproduction |
| what are chromosomes | There cellular structures found in the nucleus composed of protein and DNA |
| Interphase | Is the longest part. Everything happens here except for division (cell growth, protein production, etc. Genetic material is copied and long strands of DNA called chromatids coil into thinker chromosomes attached by a centromere |
| Prophase | Is when the nuclear membrane and nucleolus disappear. Centrioles separate from each forming spindle fibres which control movement of chromosomes by attaching to the centromeres |
| Metaphase | The spindle fibres position the chromosomes in a line across the middle of the cell |
| anaphase | Spindle fibres contract and get shorter, centromere gets pulled apart sending chromosomes to opposite directions from their copies |
| telophase | chromosomes reach their pole, spindle fibres disappear and nuclear membrane begins to reform around each pair of chromosomes. Nucleoli appear in each new nucleus and cytoplasm starts to divide |
| cytokinesis | Cytoplasm fully divides and 2 genetically identical cells form |
| mitosis | refers to the stages of the cell cycle when the genetic material is dividing PMAT |
| sexual reproduction | is when 2 parents each provide a cell, called a gamete, and they join together to form a new cell, called a zygote. Gametes have only half the normal number of chromosomes (haploid number) |
| homologous pairs of chromosomes | The cells chromosomes are found as pairs , each pair is not identical but have the same gene type. |
| what happens when sperm and egg cells join | They each provide one member of each homologous pair |
| karyotypes | photograph/view chromosomes under a microscope and arrange them based on size and type |
| Karyotes | a picture of the chromosomes that have been arranged |
| Meiosis | Type of cell division that separates homologous pairs to produce gametes with only half the number of chromosomes |
| steps of meiosis | - starts with a normal diploid cell in interphase - Chromosomes duplicate as in mitosis - then theres 2 cell divisions |
| division 1 | The chromosomes pair up with their homologous pair and are separated from each other, they migrate to opposite poles |
| division 2 | similar to mitosis the sister chromatids separated by spindle fibres and results in 4 cells produced, each having half the number of chromosomes |
| gametogenisis | is the formation of sex cells Spermatogenesis- is production of sperm cells oogenesis is the formation of egg cells |
| Spermatogenisis | each of the 4 cells of meiosis develops a flagellum and cell contents are evenly divided among the 4. results in 4 equal sized haploid sperm cells. have a short lifespan due to the small amounts of cytoplasm and nuclear mass but have max motility |
| oogenesis | eggs must survive longer, so all cell contents are placed in 1 of 4 cells and cytoplasm doesn't divide evenly. 3 remaining become non-functional containing one chromosome so they die. The leftover one becomes a haploid ovum (egg cell) |
| genetic variation in meiosis | homologous pairs are separated at random resulting in us producing many different gametes and combos of genes |
| male and females (determining sex) | in males, one chromosome is much smaller. XY. females is two XX's |
| autosomes | chromosomes that arent sex chromosomes |
| 3 organisms that use a diff sex determination system | reptiles: sex is determined by temp of eggs during incubation FIsh: all are born male but develop into females as they grow larger/older earthworms: have both male/female reproductive organs |
| how does non-disjunction (abnormal meiosis) occur? | when homologous pairs of chromosomes fail to separate during meiosis (results in one daughter cell having an extra chromosome while another is missing one) |
| Down syndrome | Trisomy 21 -round face, short builds with thick necks - more prone to infections - 40% have heart diseases - thick tongue = difficulty speaking - short life expectancy - women in 20s have 1 in 1000 chance while in 40s have 1 in 40 |
| Turner syndrome | have one X and no Y -sterile but appear as females - short, broad chest, low ears, webbed necks - most are miscarried during pregnancy (first half) - 1 in 2500 births |
| Klinefelter syndrome | males with extra X chromosome -sterile and certain female characteristics - most common sex chromosome disorder in humans - 1 in 1000 births |
| Patau syndrome | trisomy 13 - serious development problems (brain, heart, kidneys) - babies rarely live a few months - 1 in 25 000 |
| edwards syndrome | trisomy 18 - defective organ systems - live less than one month] 1 in 6000 |
| diagnosing non-disjunction | confirmed by a karyotype. obtain sample of white blood cells which you add a solution for it to undergo mitosis, then you photograph at metaphase where chromosomes are condensed and easy to read |
| 460 - 377 B.C | Hippocrates thought all parts of the body produced seeds of parents and they fused together to form a child |
| 384 - 322 B.C | Aristotle believed male and female semen mixed during conception |
| 1500s | William harvey believed in epigenesis where embryos formed in stages were affected by factors inside and outside of mother |
| 1600s | anton van used a microscope and examined gametes, saw animalcules in semen and proposed they were preformed embryos (all genes came from the father only) |
| blending theory | suggests traits from parents blend, however theory failed to explain why certain traits skipped a generation |
| Mendel | created the backbone of genetics. he experimented with pea plants and created 2 laws of heredity used today |
| why did Mendel use pea plants | - they were available in Europe - diff plants had diff traits - sex organs were inside the flower which allowed him to control which plant fertilized which - they matured quickly |
| Mendel's first experiment | led him to believe that when opposite traits are crossed the offspring will always be dominant (F1, first filial generation). when second generation were bred (second filial generation) the dominant trait was present 75% of the time. |
Created by:
Tamara123_
Popular Biology sets