Reproduction Flashcards
1
Q
Interphase
A
Longest part of cell cycle (90% of time here).
Cells with terminal differentiation (muscle/nerve) spend all the time in G phase.
2
Q
G1 Stage (presynthetic Gap)
A
Cells create organelles for energy & protein production.
Cell doubles in size.
Must pass check point to continue to next phase.
3
Q
S stage (synthesis)
A
- Genetic material is replicated.
- Each chromosome consists of 2 sister chromatids bound by a centromere
- ploidy of cell remains the same
4
Q
G2 stage (postsynthetic gap)
A
-quality control, ensures cell has enough organelles to divide
5
Q
Mitosis (M phase)
A
- for diploid cells.
- prophase, metaphase, anaphase, telophase
- separation of chromosomes occur here
6
Q
Centriols
A
- organelles located outside nucleus in region called centrosome.
- ensures proper movement of chromosmes
- during prophase, they migrate to opposite poles and form spindle fiber.
7
Q
Spindle fiber
A
Made of microtubles and have attachment points known as asters for chromosomes to attach to when dividing.
8
Q
Prophase
A
- chromosomes condense.
- spindle apparatus forms between centriols
- Nuclear membrane dissolves.
9
Q
Metaphase
A
-Chromosomes line in the middle- called the metaphase plate.
10
Q
Kinetochores
A
Proteins on chromatids that attach to spindle fibers
11
Q
Anaphase
A
Sister chromatids are separated by shortening of the kinetochore fibers.
12
Q
Telophase
A
Spindle apparatus disappears and a nuclear membrane reforms around each set of chromosomes.
13
Q
Cytokinesis
A
Separation of the cytoplasm and organelles to daughter cells.
14
Q
Asexual Reproduction
A
- offspring from a single parent
- 4 types: Binary fission, Budding, Regeneration, and Parthenogenesis.
15
Q
Binary Fission
A
- circular chromosome attaches to cell wall & replicates & cell grows in size.
- eventually plasma membrane and cell wall grow inwards.
- rapid process, and not as diverse.
- in prokaryotes
16
Q
Budding
A
- Equal replication but unequal cytokinesis
- In hydra and yeast (eukaryotes)
17
Q
Regeneration
A
- Entire body part can be regrown from a part.
- example is a tail in a lizard, and liver in humans
18
Q
Parthenogenesis
A
- process when an adult organism develops from an unfertilized egg.
- they are haploid in number of chromosomes.
- occurs in insects.
19
Q
Sexual Reproduction
A
- offspring are genetically unique
- cells that contribute to this are gametes.
20
Q
Gametes
A
-Haploid cells that are produced through meiosis.
21
Q
Meiosis
A
- process of developing 4 different haploid gametes.
- occurs in gametocytes.
- 2 rounds of division
22
Q
Meiosis I
A
- known as reductional division where homologous chromosomes are separated.
- generates haploid daughter cells..
23
Q
Meiosis II
A
- known as equational division.
- similar to mitosis
- results in separation of sister chromatids.
24
Q
Meiosis I- prophase I
A
-here homologous chromosomes come together and intertwine, in a process called synapsis.
25
homologous chromosomes
-contain 4 chromatids, referred to as a tetrad.
26
Chiasma
part of chromosome that breaks during synapsis
27
Crossing over
process of DNA exchange that results the sister chromatids to be different.
Only occurs between homologous chromosomes, not sister chromatids
results in genetic diversity!
28
Meiosis I-Prophase I
-tetrads align at metaphase plate and each pair is separated.
29
Anaphase I
- process called disjunction because either chromosome may end up in either daughter cell.
- distribution of homologous chromosomes to the two intermediate daughter cells is random with respect to parental origin.
30
Telophase I
- nuclear membrane forms around each new nucleus.
| - new nucleus is now haploid since half the genetic info is contributed to each daughter cell.
31
Meiosis II
- Very similar to mitosis.
| - Occurs to both daughter cells from Meiosis I so it results in 4 haploid daughter cells per gametocyte.
32
Gonads
- produce haploid cells (sperm/ovum)
| - derived from same embryological structure in female and male
33
Testes
- primitive gonad in male.
| - seminiferous tubules & interstitial cells (cell of leydig)
34
Seminiferous tubules
produce sperm.
35
Sertoli cells
Nourish sperm
36
Interstitial cells/ cells of leydig
secrete testosterone and other androgens
37
Scrotum
- external pouch that hangs below the penis
- testes are located here
- maintains a temperature 2/4 degrees below the body (essential for sperm production b/c of enzymes)
38
epididymis
-mature sperm are stored here until ejaculation.
39
Ejaculation
sperm travel through the ejaculatory duct and urethra and exit the body thru the penis.
40
Seminal vesicles, prostate glad, and bulbourethral gland
produce a seminal fluid in which sperm pass through with it.
-this mix is to nourish the sperm (with fructose) and allow basic properties so sperm can survive in the acidic environment of female reproductive tract.
41
Semen
Combination of sperm and seminal fluid.
42
Pathway of sperm creation/ejaculation SEVEN UP
```
Seminiferous tubules
Epididymis
Vas deferens
Ejaculatory duct
(Nothing)
Urethra
Penis
```
43
spermatogenesis
- the formation of haploid sperm through meiosis.
| - occurs in seminiferous tubules.
44
Spermatogonia
diploid stem cells in males
45
Primary Spermatocytes
diploid cells developed from differentiation of spermatogonia
46
Secondary spermatocytes
First Meiotic division of primary spermatocytes results in these.
-Cells are haploid
47
Spermatids
-Results of meiosis II of secondary spermatocytes
48
Spermatozoa
-maturation of spermatids results in this.
49
Mature spermatozoa structure
- Head (genetic material)
- midpiece (generates energy-mitochondria)
- Tail (motility)
50
Acrosome
cap that covers the head of the sperm
| derived from golgi and is needed to penetrate the ovum.
51
Ovaries
- Gonads in female
- produce estrogen and progesterone
- consists of thousands of follicles.
52
Follicles
multilayered sacs that contain, nourish, and protect immature ova.
53
Fallopian Tube/oviduct
lined with cilia that allows one egg per month to go to the uterus.
54
Uterus
muscular, site of fetal development.
55
Cervix
lower end of uterus and connects to vaginal canal
56
Vaginal canal
Site of sperm deposit during intercourse.
57
Vulva
the external female anatomy.
58
oogenesis
production of female gametes
59
oogonia
a limited amount of cells formed during fetal development.
60
Primary oocytes
predifferentiated cells females already have at birth
| diploid cells that are frozen in prohphase I.
61
Secondary oocyte
Once woman reaches menarch, one primary oocyte per month will complete meiosis I producing secondary oocyte (haploid)
remains frozen in metaphase II and does not complete the remainder of meiosis II unless fertilization occurs
62
zona pellucida and corona radiata
two cell layers around oocytes.
63
Mature ovum
a large cell consisting of large amounts of cytoplasm and organelles.
64
Acrosomal apparatus
a tubelike structure formed by sperm once it comes into direct contact with the secondary oocyte's membrane. allowing for nucleus to fuse
65
cortical reaction
reaction the ovum undergoes once nucleus fuse.
| release of Calcium
66
Fertilization membrane
a membrane that is impenetrable to other sperm to prevent multiple fertilizations.
