Reproduction Final Flashcards
What are the 3 components of the circulatory system
fluid, pump, vessels
what is the purpose of circulatory system in animals
high metabolic demands
work over long distances
who has no circulatory system?
- Protozoans
- Porifera
- Cnidaria
- Ctenophora
- Platyhelminthes
- Nematoda
who has a closed circulatory system
Cephalopod molluscs
• Annelids
• Chordates
who has an open circulatory system
- Most molluscs
- Arthropods
- Echinoderms
- Hemichordates`
where does gas exchange occur
capillaries
what are the 2 types of vessels?
- oxygenated blood leaves heart through arteries
* deoxygenated blood returns to heart through veins
what is the pump in fish
- Two chambers (1 atrium and 1 ventricle)
* Single loop circulatory system
what is the pump in amphibians and reptiles?
- Three-chambers (2 atria, 1 ventricle)
- Double loop circulatory system
- Some mixing of de-oxygenated and oxygenated blood
what is the pump in aves and mammals
- four-chambers (2 atria, 2 ventricles)
- Double loop circulatory system
- Most efficient
two types of reproduction?
r selected and k selected
r selected
- short life expectancy
- Many offspring (thousands)
- Low % survival
- No parental care
- Cultural memes not passed down
- no parental nourishment
k selected
- Long life expectancy
- Few offspring
- High % survival
- Parental care
- Cultural memes passed down
- Nourish embryo
what are the 5 types of asexual reproduction?
:)
what are the 3 types of sexual reproduction?
bisexual reproduction
hermaphroditism
parthenogenesis
sequential hermaphroditism
active sex changes at some point during life
simultaneous hermaphroditism
active female and male organs at the same time
what are the types of parthenogenesis
diploid and haploid ( meiosis forms a haploid egg cell, which develops into a haploid individual)
automixis vs apomixis
In automixis, meiosis forms the haploid oocyte, which fuses with another oocyte or undergoes chromosome replication to form a diploid zygote.
In apomixis, mitosis produces a diploid female egg cell
automixis does not produce a clone, apomixis produces a clone
what are the common reproductive strategies of fishes?
dioecious, external fertilization, oviparous, release large numbers of gametes
what are the general fish reproductive patterns
Pelagic (open sea) marine teleosts
Near-shore and benthic (bottom-dwelling) fish
near-shore and benthic fish
- Larger eggs, with more yolk
- Non-buoyant, adhesive
- Eggs are buried, attached to vegetation, deposited in nests
- Many benthic fish guard their eggs (male)
Pelagic marine teleosts
- minute, buoyant, transparent eggs
* Eggs hatch into larvae as they float in the ocean
reproductive traits in birds
dioecious, oviparous, generally no external genitalia, cloaca, internal fertilization by a cloacal kiss, female lays one egg per day until she has a full clutch
determinant layers
produce a certain number of eggs and then stop
indeterminate layers
replace eggs if some are removed
polygyny
one male, many females
females tend to choose the dominant male
males defend individual territories and display
polyandry
many males, one female
female will lay many clutches of eggs which individual males care for
precocial
- Hatch covered with down
- Can run or swim as soon as they hatch
- Most can’t fly (one exception: brush turkeys of Australia)
- Fairly independent, but still fed and protected from predators for some time
altricial
- Smaller eggs, less yolk (less investment) • Hatch naked
- Unable to see or walk at hatch
- Remain in the nest for 1-2 weeks or more • Must be fend constantly by parents
reproductive traits in mammals
Defined mating seasons
Delayed implantation lengthens the gestation period in some mammals
Male mammals fertile at any time; Timing of female fertility is restricted by the estrous cycle
estrous, monoestrous, polyestrous, menstruation
estrous - period of heat of a female mammal associated with ovulation
Monoestrous: single estrus during breeding season
Polyestrous: recurrence of estrus during breeding season
mammalian reproductive strategies?
Monotremes
Marsupials
Placental Mammals
monotremes
• Large, yolky eggs, leathery shell
• Earliest mammals laid eggs, and monotremes have retained this characteristic
drink milk
Marsupials
• Embryos develop in mother’s uterus but do not implant
• Born at a premature stage; complete development outside of uterus
-viviparous, premature birth
-transient placenta (yolk sac placenta)
-short gestation
-lactation and parental care is long
Placental Mammals
• 94% of mammals are placental
• Embryo is nourished through the placenta in the uterus
-viviparous
-prolonged gestation
-gestation period increases with size of the animal
Mammal young can be…
- altricial (immature and helpless)
* precocial (mature and mobile)
what is the structure of the placenta?
• Amnion surrounds embryo with amniotic
fluid (as in other animals)
• Allantois, yolk sac, and part of chorion contribute to the placenta
• Chorion surrounds entire thing and breaks as labour begins
- The placenta is a modified amniotic egg
what reproductive strategies produce larger eggs?
Benthic
precocial
