exam 3 Flashcards
1
Q
unicellular organisms reproduce by
A
dividing
2
Q
zygote
A
fertilized egg
3
Q
mitosis
A
cell division that caries out same gene sequence of bases ( A,T,G,C)
4
Q
gene is code to build a…
A
polypeptide (protien)
5
Q
cell cycle phases
A
M phase (mitosis and cytokinesis)
Interphase
-G1 (growth)
-S (growth and DNA replication)
-G2 (growth and final preparation for cell division)
6
Q
epithelial cells (skin)
A
constantly replace and divide
7
Q
liver cells replucate only when
A
damage occurs
8
Q
cells that cannot divide in adult humans are ___ and ___
A
muscle cells and nerve cells
9
Q
decision for a cell to divide is made in what phase
A
G1 phase
10
Q
what phase is non dividing stage
A
G0
11
Q
metastasis
A
mutated cells enter ectracellular fluid and start growth at a new site in body (cancer)
12
Q
somatic cells
A
all cells of an organism besides sex cells
they have 46 chromosomes
13
Q
reproductive cells
A
sperm and egg
have 23 chromosomes
14
Q
chromatin
A
“opened up” version of a chromosome, accessible for copying or making protien
15
Q
a pair of similar chromosomes are called
A
homologous
16
Q
homologous chromosomes have ___ traits
A
different variations of same trait
ex. blue eye vs brown
17
Q
meiosis produces
A
gametes
18
Q
haploid (n)
A
23 chromosomes
gametes
19
Q
diploid (2n)
A
zygote and all other cells
46 chromosomes
20
Q
sister chromatids
A
an original chromosome and a copy
they are identical
21
Q
cytokinesis
A
at the end of mitosis the cell splits in 2 (identical)
22
Q
early prophase (mitosis)
A
nuclear envelope (membrane) breaks down and chromatin condense to become chromosomes
23
Q
centrioles
A
microtubule organizing centers present in early prophase form miotic spindle (for DNA)
24
Q
prophase
A
mitotic spindle continues forming 2 sister chromatids joined by a centromere are pulled apart and mitotic spindle completes formation
25
centromere
joins sister chromatids together
microtubules of spindle attach to pull sister chromatids apart move to opposite poles
26
metaphase
centrioles arrive at opposite poles chromatid pairs line up at metaphase plate (middle of cell)
basically looks like dna now 💀
27
anaphase
sister chromatids split and migrate to oppsite poles
28
telephase
cell elongates and nuclear envelope forms around daighter chromosomes
chromosomes decondense into chromatin state
mitosis is complete
29
cytokinesis
after telephase cell is pinched in 2
30
animal cytokinesis
divides the cell using cleavage
actin and myosin create fibers that form a belt around cell
31
plant cytokinesis
forms a cell wall called cell plate
32
fission
prokaryotic reproduction (bacteria)
creates identical copies
33
gene
a sequence of DNA nucleotides that code how to build polypeptides
34
gene expression
dna in a gene is being used to make protien
35
interphase 1
each chromosome replicates to be 2 joined sister chromatids
36
prophase 1
chromosomes condense and attach to nuclear envelope, non sister strands may cross (crossing over)
37
crossing over
during prophase (synapsis) non sister stands cross during pairing, it increases genetic variety
38
synapsis
during prophase 1 homologous chromosomes pair up
39
metaphase 1
chromosomes line up at metaphase plate and independent assortment occurs (increase genetic variation)
40
anaphase 1
chromatids migrate to poled but STAY JOINED AT CENTROMERE
41
telephase 1
cell splits in 2 no replication of DNA occurs before daughter cells divide again
42
prophase 2
spindle apparatus forms, chomosomes move to metaphase plate
43
metaphase 2
chromosomes line up at metaphase plate and attack to microtubules on opposite poles
44
anaphase 2
sister chromatids seperate, move to opposite poles
45
telephase 2 and cytokinesis
nucleoli and nuclear envelope reappear
cytokinesis occurs
(result 4 daughter haploid cells)
46
oogenasis and spermatogenesis
creating ovum and sperm
47
fractions
seperated bacteria to avoid harmful nucleic bacteria from transforming harmless bactera
48
bacteriophages (phages)
viruses that infect bacteria
49
virus
DNA surrounded by a protien coat
50
double helix dna base pairing
A + T , C + G
paired together by hydrogen bonds
51
antiparallel
2 strands of double helix are alligned differently and run different directions (opposite)
3->5
5->3
52
DNA is copied by...
pulling apart 2 strands and adding complimentary bases (semiconservative)
53
semiconservative
dna copying using one strand of parent double helix for 2 daughter double helicies
54
helicases
enzyme that unwinds and open DNA strands
single strands are stablized by single strand binding protiens
55
origin of replication
where DNA replication begins
56
dna repl. initiation occurs when...
primase enzymes attach a few new bases to open strands using a DNA primer, since primer is not DNA it will be removed later and replaced w DNA
57
elongation of strand is carried out by...
DNA polymerases, they only bind when primer is present
this will make the new strand of DNA
58
leading strand
adds bases as DNA elongates using polymerase 3, no gaps in leading strand
59
lagging strand
bases are added backward from the fork opening, RNA primers removed using polymerase 1, gaps are filled by DNA ligase
60
allele
gene
61
mendel
choose either or traits
62
hybridization
crossing 2 plants w different traits
63
law of segregation
pair of alleles will segregate so each gamete only carries 1 member (gene)
64
homozygous
same gene on each chromosome
ex TT
65
heterozygous
different genes on each chromosome
ex Tt
66
phenotype
organisms appearance
ex blue eyes
67
genotype
organisms actual genes
ex. brown eyes with Tt gene
68
law of independent assortment
random genetics
69
dihybrid
crossing 2 different traits for 2 different characters at once
TTGG x ttgg
70
offspring phenotype ratio
9:3:3:1
71
incomplete dominance
both traits are equal
1:2:1
72
polygenic inheritance
bell shaped curve
73
sex linked disorders
color blindness
hemophilia- excessive bleeding
74
nondisjunction
gamete gets an extra chromosome
ex down syndrome
75
pedigrees
family history
76
mutations
random changes in sequence of DNA nucleotides that make a gene
77
amniocentesis
using a needle to take amniotic fluid to test for gene abnormalities
78
chorionic villi sampling
removing cells from chorion to test for gene abnormalities
79
budding
babys grow on animal and when its large enough attachment is severed
80
semineferous tubules
sperm forms
81
epidydymis
carries sperm from seminiferous tubules to vas deferens
82
vas deferens
transport sperm to ejaculatory duct small amount of fluid is added here
83
seminal vesucles
create 60% of seminal fluid (alkaline)
fructose is also present
84
prostate gland
contains citric acid to give sperm energy
85
estrogens
estradiol, estrone, progesterone
86
ovulation completes...
meiosis 1 and meiosis 2 doesnt begin until fertilization
87
corpus luteum
releases hormones that control menteal cycle
88
endometrium
embryo implants and is mourished there until placenta develops
89
myometrium
contacts during labor
90
ovarian menstrual cycle
folicular phase
luteal phase
mentrual cycle
91
follicular phase
W1 FSH and LH lvls rise
FSH causes cell to complete meiosis 1
92
luteal phase
LH causes ovulation and repairs cells around egg (follicle)
corpus luteum secretes progesterone
93
uterine (menstrual) cycle
progesterone thivkens endometrium of uterus
if egg is fertilized it can get nourishment
if not blood rich tissue is shed
94
acrosomal reaction
soerm penetrates egg :D
95
cortical reaction
once sperm enters egg immediately hardens again to prevent it from getting fertilized again
96
after fertilization...
cleavage occurs cell begins splitting
97
morulation
cell divides, morula stafe ovcurs ,solid ball of cells
98
blastulation
hollow ball of cells called blastula... it attaches to endometrium
99
implantation occurs day..
6
100
grastulation
3 different cell types develop
ectoderm
mesoderm
endoderm
101
ectoderm
skin inner ears nerve tissue
102
mesoderm
muscles skeleton
103
endoderm
lining of digestive tract lungs liver
104
chorion
surrounds embryo and eventually creates placenta
allows fas exchange without water loss
105
amnion
dome surrounds embryo and is filled with fluid, this water breaks during birth
106
yolk sac
fetal blood cells that move to embryo and use as food source for a little while
107
allantois
forms umbilicat cord carrients nutrients from placenta and excretes wastes
108
placenta
moves material from mom to baby without exchanging blood supllies through diffusion
