XII Chap 1 Reproduction of Living Organisms Flashcards
Life span of the following: tortoise crocodile butterfly crow parrot
tortoise - 100-150 years crocodile - 60 years butterfly - 1-2 weeks crow - 15 years parrot - 140 years
Life span of the following: elephant dog banana tree horse banyan tree
elephant - 60 to 90 years dog - 20 to 30 years banana tree - 25 years horse - 20-25 years banyan tree - 200-500 years
Life span of the following: rose fruitfly rice plant cow
rose - 5-7 years
fruitfly - 30 days
rice plant - 3-4 months
cow - 20-25 years
Single-celled organisms die a natural death. True or False?
False
Define reproduction
biological process;
organism produces offspring;
continuity of species
What is sexual reproduction and asexual reproduction?
sexual: 2 parents (opposite sex), infusion of male & female gametes
asexual: single parent, with OR without gametogenesis
In asexual reproduction, offsprings are clones of each other but not of their parents. True or False
False; clones of parents as well, morphologically and genetically
Asexual reproduction is common in ___________________
unicellular organisms and simple plants and animals (i.e. some invertebrates)
How does asexual reproduction occur in Protists and Monerans?
Cell division by mitosis
How does asexual reproduction occur in fungi and simple plants?
Special microscopic motile structures e.g. zoospores
Define binary fission. How is budding different?
BF - Cell divides into 2 halves; budding - unequal division, small buds that separate and grow
How do amoeba reproduce?
Asexually by binary fission; but when unfavorable conditions then withdraws pseudopodia and secrets 3-layered cyst (encystation), when favorable conditions return, then Amoeba divides by fission => pseudopodiospores => cyst wall bursts => spores liberated (sporulation)
How does yeast reproduce?
Asexually by budding
How does paramecium reproduce?
Asexually by binary fission
What is encystation?
When amoeba secretes 3-layered cyst to envelope and protect itself during unfavorable conditions
What are pseudopodiospores?
many minute amoeba produced during multiple fission (asexual reproduction)
What are zoospores?
microscopic
motile structures
in asexual reproduction
of fungi and some small plants / animals
most common structure
What are some of the special asexual reproductive structures created by members of Fungi and simple plants?
Zoospores (most common), conidia, gemmules, buds
What special reproductive structure is used by Penicillium?
conidia
What special reproductive structure is used by Chlamydomonas?
zoospores
What special reproductive structure is used by Hydra?
buds
What special reproductive structure is used by sponges?
gemmules
In animals (or other simple organisms) the term asexual is used when describing reproduction, in plants the term is _________
vegetative reproduction
What is asexual reproduction in plants called? What are the various propagules?
Vegetative propagation
Runner, rhizome, sucker, tuber, offset, bulb
What do tomato, sunflower, tulip, mustard and daffodil have in common ?
They are all bisexual plants
Define fragmentation?
Asexual reproduction
body breaks into different segments
each fragment grows into an adult
e.g. Hydra
Which plant is known as the “Terror of Bengal”?
water hyacinth
What does asexual reproduction look like on potato?
Buds emerge from the “eyes” (node) of the modified stem
What does asexual reproduction look like on Bryophyllum?
adventitious buds on leaves aka leaf buds
What vegetative propagules are used in water hyacinth?
offset
What vegetative propagules are used in ginger and banana?
rhizome
adventitious roots for ginger
What vegetative propagules are used in Agave?
Bulbil
Organisms with simple organisation are commonly sexual but before the onset of adverse conditions they turn to asexual reproduction. True or False?
False; the other way around
Higher plants only reproduce sexually. True or False?
False, asexually and sexually
Most animals reproduce only sexually. T or F?
True
Sexual reproduction consists of 3 events
Pre-fertilization, fertilization, post-fertilization
A single individual can reproduce sexually. True or False?
True if can produce male and female gametes
Define sexual reproduction
Non-identical offspring;
more complex and slower process than asexual reproduction
involves fusion/fertilization of M & F gametes; formation of zygote; embryogenesis
Animals can reproduce during the juvenile phase. T or F?
False, only after
Juvenile phase is called the ______ phase in plants
vegetative
_______ shows that higher plants have come into their reproductive phase
Flowering
Mature phase is aka as ________ phase
senescent
______ plants have clear reproductive phases;
______ plants reproduce year-long, its hard to identify distinct phases
Annual & biennial => clear phases;
Perennial => hard to identify
Some flowering plants reproductive phases are seasonal, some flower year-long and some after X number of years or even only once in their lifetime. True or False?
True
What plant flowers only once in their lifetime?
Bamboo (after 50-100 years)
Which plant flowers once in 12 years?
Strobilanthus Kunthiana (neelakuranji)
In animals, ______ changes occur after the juvenile phase and before the active reproductive phase
morphological and physiological
Birds in nature lay eggs seasonally. True or False?
True
Define oestrus and menstrual cycles. What is the difference between the two?
Cyclical changes in ovaries, accessory ducts and hormones - female mammals - can be seasonal or continuous
Oestrus - non-primate
Menstrual - primate
Order the phases correctly:
Birth Death Reproductive Senescence Vegetative
What’s responsible for the changes between these phases?
Birth -> Vegetative -> Reproductive -> Senescence -> Death
Hormones
Hormones are responsible for the changes between reproductive and non-reproductive phases in both plants and animals. T or F?
True
What are the 2 pre-fertilization events?
Gametogenesis and Gamete transfer
Define gametogenesis
formation of 2 gametes, which are always haploid cells
Differentiate between isogametes and heterogametes
Isogametes = aka homogametes, so similar you cannot distinguish between them (e.g. some algae)
Hetero = morphologically distinct gametest e.g. humans, most organisms
What are the male and female gametes?
Male - antherozoid / sperm
Female = ovum / egg
What type of gametes (iso/hetero) do these organisms have:
Cladophora (alga)
Fucus (alga)
Homo sapiens
Cladophora (alga) - isogametes
Fucus (alga) - heterogametes
Homo sapiens - heterogametes
Chara is a monoecious or dioecious plant?
Monoecious
Marchantia is a monoecious or dioecious plant?
Dioecious
Sweet potato is a bisexual or unisexual plant?
Bisexual
What is a hermaphrodite? What are 3 other words associated with it?
An organism that has both male and female reproductive structure in the same body
Other words - bisexual, monoecious, homothallic
What is a unisexual plant/animal?
male and female reproductive parts in DIFFERENT plants/animals - need 2 different individuals for sexual reproduction
What 2 words are used to denote the bisexual nature of plants / fungi? unisexual?
Bisexual - homothallic and monoecious
Unisexual - heterothallic and dioecious
What are the male and female flowers called?
Staminate (contains stamens)
Pistillate (contains pistils)
Categorize the following into monoecious and dioecious: Papaya Cucurbits Coconuts Date palm
Papaya - dioecious
Date palm - dioecious
Cucurbits - monoecious
Coconuts - monoecious
Sponge, tapeworm, leech and earthworms are all unisexual animals. True or False?
False, bisexual / hermaphrodites
Cockroaches, like humans, are unisexual animals. T or F?
True
Gametes are always diploid, but parents may be haploid or diploid. T or F?
False, always haploid
parents bit is correct
Haploid parents produce diploid gametes,
Diploid parents product haploid gametes.
T or F?
False, either always produces haploid gametes
Haploid parents undergoes _______ kind of cell division to produce gametes
Mitotic
Diploid parents undergoes _______ kind of cell division to produce gametes
Meiosis
Which organisms have diploid parents?
Pteridophytes, Gymnosperms, Angiosperms, and most animals
Which organisms have haploid parents?
Kingdom Monera, Fungi, Algae and Bryophytes
Organisms of Pteridophytes, Gymnosperms, Angiosperms and most animals have _____ parents. Haploid or Diploid?
Diploid
What are meiocytes and where are they found?
Specialized gamete mother cells in diploid organisms
When they undergo meiosis -> one set of chromosomes in each gamete
What is the relationship b/w the # of chromosomes in meiocytes and gametes?
meiocytes = 2n gametes = n
Male gametes and female gametes are both motile in all higher order organisms like animals. T or F?
False, only in few fungi and algae
Otherwise, male - motile, female - stationary
Water is a medium of gamete transfer in what kinds of organisms?
Simple plants - algae, bryophytes, pteridophytes
Male gametes need a _____ to move through.
Examples?
Medium
algae, bryophytes, pteridophytes - water
Number of female gametes are 1000 times that of male gametes since female gametes are weak and may die. True or False.
False - reverse, to make up for loss in transfer
Pollen grains carry male gametes produced in _______ and deposit them on the ______
anther;
stigma
Unisexual plants are self-fertilising. True or False?
False; bisexual are self-fertilizing;
unisexual plants transfer gametes through pollination
Peas a bisexual or unisexual?
Bisexual
What is pollination?
Facilitation of transfer of pollen grains;
way for unisexual/dioecious plants to reproduce
What is fertilization?
Fusion of gametes (syngamy) to produce a diploid zygote
What happens after pollen grain is transferred to stigma?
Pollen grain land and germinate on stigma, pollen tubes grow down the style carrying male gametes to ovule and discharge the gamete near the egg;
Define syngamy
fusion of gametes resulting in diploid zygote
Define pathenogenesis with examples
Female gamete forms new organism without fertilization
e.g. rotifer, honeybee, lizard and turkey (bird)
External vs internal fertilization
External - syngamy outside female body (often in water);
mostly in aquatic organisms (algae, fishes, amphibians);
great synchrony between sexes;
large # of male gametes released
large # of offspring, many of which don’t survive due to predators
Internal - inside (mostly female) body;
terrestrial organisms (fungi, reptiles, birds, mammals, bryophytes, pteridophytes, gynosperms, angiosperms);
male gamete is motile to reach egg (except seed plant);
large # of male gamete but fewer number of eggs
What are the post fertilization events?
Embryogenesis
Formation of diploid zygote is universal in all sexually producing organisms. T or F?
True
Describe zygote development in fungi and algae
Thick wall resistant to desiccation or damage;
period of rest before germination
What happens post zygote formation in organisms with haplontic life cycle?
Zygote divides by meiosis -> haploid spores -> grow into haploid individuals
Zygote begins as a single cell organism. T or F?
True
What is embryogenesis?
Zygote -> embryo
Cell division by mitosis (=> increase in number of cells) and cell differentiation takes place
Oviparous vs Viviparous
Ovi - external development; eggs of birds and reptiles; hard calcareous egg shell; laid in safe place in environment; incubated and hatched
Viviparous - internal development; most mammals; greater chance of survival than ovi
On what basis is the differentiation done between oviparous and viviparous?
Where zygote development (embryogenesis) takes place - externally or internally
Describe embryogenesis in flowering plants
Zygote inside ovule;
sepals, petals, stamens fall off but pistil is still attached;
Zygote -> embryo;
Ovules -> seed;
Ovary -> fruit with pericarp (thick protective wall);
seeds are dispersed which germinate in new places into new plants
_______ and ______ are the most common asexual structures in several algae and fungi
Zoospores and conidia
_______ and ______ are the most common asexual structures in lower animals
Budding and gemmules
Prokaryotes and unicellular organisms reproduce how?
asexually by cell division or binary fission
Post-fertilization events include:
formation of zygote and embryogenesis
Sexuality is varied in angiosperms due to _____
production of diverse types of flowers
Transfer of male gametes in unisexual organisms happens by _______
copulation or simultaneous release
_______ is the progenitor of the next generation
Embryo
Cucurbit is a monoecious plant that has ________ (bisexual or unisexual) flowers?
unisexual; staminate flowers - bright yellow;
The most critical event in sexual reproduction?
Gametogenesis - gamete transfer - fertilization - embryogenesis
Fertilization
Rotifers are ?
animals capable of reproducing by parthenogenesis
flowers are unisexual in:
pea - cucumber - china rose - onion
cucumber
In vegetative propagation, when _____ comes in contact with damp soil or water, they produce roots and new plants
shoot - node - axial shoot - roots
Node
because vegetative propagation!!
Parthenogenesis is development of an organism directly from:
female gametes - vegetative cells - fertilized ovum - none of the above
female gametes (rotifers, honeybees, lizards and turkey)
Organisms in which both male and female gametes are motile
algae - fungi - fish - algae & fungi
algae & fungi
