Biology 102 Final Flashcards
karyotype
- picture of chromosomes
- chromosomes come in pairs (n = 23 and humans have 2n)
gametes
- haploid cells
- one set of chromosomes (1n)
sexual reproduction
- offspring are genetically different from parents/each other
meiosis
- cell division to produce sex cells
- diploid to haploid cells
independent assortment
every chromosome orients independently of others during meiosis
crossing over
- pieces of homologous non-sister chromatids exchange
- translocation
SRY gene
- sex determining region of Y chromosome
- ovaries develop as default unless told otherwise
non-disjunction, meiosis I
- problems with homologous chromosome separation
non-disjunction, meiosis II
- homologous chromosomes separate but sister chromatids do not
DNA sequence problems/mutations
- down syndrome
- XXY > Klinefelters [male]
- XXX > Metafemale
- XO > Turners syndrome [female]
pedigree
history of a trait in a family > upside down family tree
phenotype
- external characteristics expressed
- shown on pedigree
genotype
- genetic makeup
- might carry a certain trait but never express
incomplete dominance
- dominance is incomplete > in between phenotype with heterozygote
- i.e. wavy hair is in between curly and straight > both traits expressed
codominance
- both alleles contribute to expression of the gene
- no dominance > work together
- i.e blood type > A, B, AB
polygenic inheritance
- certain traits affected by multiple genes
- i.e. skin color affected by 3 different genes
asexual reproduction
- 1 parent produces genetically IDENTICAL offspring
- multiply quickly, no partner, isolation is not an issue, no disease/diversity
- same genotype can cause issues since 1 disease can wipe out the population > no diversity/growth
sexual reproduction
- fusion of gametes from two individuals [humans = egg & sperm]
- advantage = genetic variability
- disadvantage = find a mate
internal fertilization
- occurs with the female body
external fertilization
egg & sperm released into the open and hope they find each other
bacterial STDs/STIs
- can be treated if detected early without long-term effects
- i.e. Chlamydia, Gonorrhea, Syphilis
fungal
- can be treated
- candidiasis
protists
- can be treated
- i.e. Trichomonaisis
viral STDs/STIs
- treatment but no cure
- i.e. HIV/AIDS, genital warts, genital herpes, hepatitis B
male reproduction
- testes produce sperm
- epididymis stores sperm
- vas deferens transports sperm
- vasectomy > cut the tube
sperm
- put in seminal fluid that is produced in seminal vesicle
- prostate gland also produces seminal fluid (30%)
- travel through urethra and out
- hormones secreted by anterior pituitary signal sperm production
female reproduction
- anterior pituitary releases FSH [follicle stimulating hormone] > follicle growth > progesterone from corpus luteum tells pituitary not to release FSH or LH because female might be pregnant > estrogen communicates with pituitary to send LH
ovary
- releases estrogen > affects uterus
- LH sent > oocyte released > corpus luteum (oocyte scar tissue) release progesterone to keep padding endometrium
uterus
- relayed info from estrogen [ovaries] thickens lining [endometrium]
- scar tissue dies with no sperm > no progesterone > lining thins/sloughs off > cycle starts over
birth control - gametes don’t meet
- celibacy/absinence
- rhythm method > can track it but body can be unpredictable
vasectomy
cutting of the vas deferens > still have ejaculate but no sperm
tubal ligation
cut and tie fallopian tubes/oviducts/uterine tubes
birth control - stopping sperm
- condom [male/female]
- diaphragm
- pulling out > not usually effective [precum]
birth control - sperm killed
spermicide
birth control - no ovulation
- pill
- patch
- injectable
- certain levels of estrogen/progesterone
- trick body into thinking it’s pregnant > shut down FSH & LH
birth control - no implantation
- intrauterine device (IUD)
- morning after pill
Fertilization
- oocyte and sprem meet > become zygote > up to 8 cell stage they are totipotent (all 8 could become humans)
- identical multiple birth pregnancy
tubal pregnancy
- zygote implants in fallopian tube
- not viable > could be life threatening if tube bursts > child will not survive
embryonic development
- placenta connects to embryo via umbilical cord
fetal alcohol syndrome
- mild to severe handicap
- caused when woman drinks/smokes/does drugs while pregnant
prenatal detection > non-invasive
- ultrasound
- maternal blood sampling
prenatal detection > invasive
- Chorionic villus sampling (CVS)
- amniocentesis > test amniotic fluid
labor process
- oxytocin released from hypothalamus/ posterior pituitary
- causes muscle contractions in uterus
- baby’s head presses on cervix
- delivery of baby through cervix/vagina pushed via uterine contractions from oxytocin
- cycle broken once baby is born
- uterus expels placenta
labor
- positive feedback process
- 3 stages
