Unit Two Flashcards
(20 cards)
Asexual reproduction benefits and disadvantages
Advantages: fast and energy efficient, colonization, and preserves traits
Disadvantage: lack of genetic , variation, mutation compounds, and vulnerability to environmental changes
Sexual reproduction benefits and disadvantages
Advantage: genetic variation, adapts to environmental changes, and reduced risk of disease
Disadvantages: time and energy consuming, fewer offsprings, and potential for inbreeding
Describe the stages of mitosis and cytokinesis
Prophase- Nuclear membrane dissolves, spindle fibres&sister chromatids form, and centrosomes migrate to opposite sides of the cell
Metaphase- Spindle fibres attach to centrosomes, then the centromere of each sister chromatid and are lined up in the center of the cell.
Anaphase- Centrosomes pull spindle fibres to the ends of the cell and pull the sister chromatids apart
Telophase- Nuclear membrane forms around each new set of chromosomes and spindle fibres dissolve
Cytokinesis- Cell membrane causes daughter cells to separate and they now both enter the cell cycle again
What’s the end result and purpose of mitosis?
Creates 2 genetically identical diploid cells
Purpose is to divide for growing and repairing damaged body cells
What’s the purpose and end result of meiosis?
Purpose is to create gametes that are used for reproduction
Ends in 4 haploids cells that are a combination of chromosomes from mom and dad. None are genetically the same
How many chromosomes do humans have?
46
List the differences between mitosis and meiosis
Mitosis Meiosis
Body cells Sex cells
One round Two rounds of
of division division
It’s cell division It’s cell
that form’s daughter division with
cells with the same four new
number of cells are
chromosomes created with
half the No genetic of chromosomes
diversity
Genetically diverse
Diploid cells(2n)
Haploid cells(n)
Asexual reproduction
Sexual reproduction
Repairs damaged Creates sex
body cells and cells used for
supports growth reproduction
Diploid is 2n?
True
What are haploid and diploid numbers referring to?
Haploid are the number of cells that only contains a single set of chromosomes (n)
Diploid are the number of cells that contain two complete sets of chromosomes (2n)
Human diploid number is 46
Human haploid number is 23
What’s Huntington’s disease?
An inherited(dominant) incurable brain disorder that causes neurons to break down
What’s trisomy?
When a gamete has an extra chromosome(24). There’s three homologous chromosomes in the place of a pair
What’s monosmy?
When there’s one less chromosome(22) in a gamete. There’s a single chromosome instead of homogeneous pair
What’s a karyotype?
Individual chromosome that’s been sorted by type and size numerically
What’s Down syndrome?
Trisomy 21
Has three copies of chromosome 21, rather than only two
What’s Turner Syndrome?
Monosomy X
When females only have one X chromosome(XO)
What’s a nondisjunction disorder?
Genetic conditions that are a result of errors during cell division, causing chromosomes to improperly separate
What’s are alleles and genes?
Allele- Different versions of genes you get from each parent
Gene- DNA pieces that give you information about how to make certain proteins and give you your traits
What’s polygenic?
Traits influenced by multiple genes
What do P1 and F1 stand for?
P1- Parental generation
F1- First filial generation
What are the types of genetic variation?
Independent assortment- When homologous pairs are separated so that one will end up in each daughter cell
Crossing over- When homologous pairs line up and their chromatids twist around each other, forming a new combination of alleles
