Bio 30 Unit 1 Final Review Flashcards
Chromatid
condensed chromosomes
Chromatin
uncondensed chromosomes
Senescence
the process of aging
Totipotent
describes a nucleus that is able to bring a cell from egg to adult
Metastasis
Cancer cells can dislodge from a tumour and move to another area
Cancer cells
cannot carry out normal functions of cells. Are almost always in mitosis.
Benign vs. malignant tumours
benign = remains at site, does not cause serious problems
malignant = may metastasize and impair functions of organs
Telomeres
Caps at the ends of chromosomes.
Reduce in length each time a cell goes through the cell cycle and divides
Telomerase
allows cancer cells to maintain telomere length
homologous chromosomes
paired chromosomes; similar in shape size and gene arrangement; are not identical
meiosis aka…
reduction division
tetrad
(meiosis) 4 chromatids
synapsis
the pairing of homologous chromosomes
Kinetochore
region of centromere that links sister chromatids to spindle
segregation
the partitioning of genetic material into two daughter cells (meiosis/reduction division)
Plant life cycle: Alternation of Generations
alternation between haploid and diploid vice versa
syndrome
a group of disorders that occur together.
down syndrome
trisomy 21. Mentally challenged, short, full face, large tongue, large forehead
Turner’s syndrome
monosomic disorder. Female that has a single x chromosome.
klinefelter’s syndrome
The child inherits the XX chromosome and Y chromosome. Appears male at birth; during puberty high levels of female sex hormones are produced
Teratogens
chemicals that cause abnormalities in embryos
Amniocentesis
an ultrasound is used to locate the position of the fetus within the mother’s womb.
A syringe draws amniotic fluid, which is spun in a centrifuge, cultured, then karyotyped.
Chorionic villi sampling (CVS)
cells are drawn from the chorionic villi (placenta). More invasive, but can be performed earlier in pregnancy.
nucleotide
phosphate, sugar, N-base
Chromosomes are made of….
DNA
DNA is made of….n
nucleotides
Segments of DNA are…
genes
DNA nitrogen bases:
Adenine, thymine, cytosine, guanine
Chagraff’s rules
amount of A=T, C=G
Rosalind Franklin
collected x-ray data on DNA
James Watson and Francis Crick
proposed a 3-D model of DNA using Franklin’s data (double helix/twisted ladder)
Backbone of (DNA) ladder
deoxyribose sugar and phosphate
What forms the rung of a DNA ladder
Nitrogen bases (ACTG). N-bases are connected by hydrogen (weak) bonds.