Science Biodiversity- Part 2 .

Reproductive strategies meaning

a method an organism uses to reproduce

Heritable meaning

The characteristic/traits which are passed down from parent to offspring, ex: hair and eye color, leaf shape, tail length.

Asexual Reproduction meaning

the formation of a new individual from a single organism- parent is cloning itself

clone meaning

an identical copy of a cell or entire organism

4 main types of asexual reproduction?

binary fission, spores, vegetative growth, budding

Advantages of asexual reproduction

-No need to spend extra energy to find a mate.

-Occurs quite rapidly therefore produces many offspring at once

disadvantages of asexual reproduction

-little to no variation

-one disease or sudden change could wipe out the entire population or species in that area

Binary Fission

the splitting of a single celled organism into 2

ex: amoeba, bacteria

Spores

a single-celled reproductive structure from which an individual offspring develops; plants, algae, fungi, and some protozoa produce spores

Budding

A bud forms an organism- eventually detaches after growth

ex: hydra, sea sponges

Vegatative Reproduction

tissues with meristems can be utilized to grow plants without the use of seeds.

what are the 4 ways of vegetative reproduction?

1. runners

2. cuttings

what are runners?

A secondary stem will grow out from the base of the main stem a distance away, it will put down roots and start to grow upwards into a new plant. may or may not be connected to og plant

EX; strawberries, spider plants

what is cutting?

In many plants, you can cut off a piece of the plant and place it in new soil to grow EX:Parsley, basil, rose, oregano

what are tubers ans bulbs?

new plants grow out of the original tuber or bulb; often more than one new plant will grow

Ex) Potatoes, tulips, daffodils

what are suckers?

when roots (often a distance away from the original plant) send up a shoot (new stem)

Ex) Aspens, roses

meristem meaning

an area of cell division containing generalized cells in the tips of roots and shoots that produce new growth in plants

Zoospores meaning

some fungi and algae sometimes produce zoospores; an asexual spore with a tail that helps it get around.

Tails allow the spore to swim around and spread genetics

Sexual Reproduction

Involves 2 parents supplying genetic material to produce offspring

Advantages of sexual reproduction

-Variation in the offspring

-survive during unfavourable conditions

- adapt to new environments

- disease is less likely to affect population

Disadvantages of sexual reproduction

-consumes a lot of energy and time

- limits the number of offspring being produced

Zygospore meaning

reproductive structure formed during sexual reproduction by a fungi; contain genetic info from both parents. Sexual reproduction occurs when spores from 2 parents fuse and form a zygospore.

Gametes

a reproductive cell containing half the number of chromosome than a somatic cell

Zygote def

a new cell formed by the process of fertilization which eventually turns into an individual

when two gametes join, the process is called...

fertilization

first step in fertilization in plants

pollen grain lands on stigma of the flower

2nd step of fertilization in plants

pollen tube forms and grows down to ovary

3rd step of fertilization in plants

sperm travels down the pollen tube to reach the egg in ovary

4th step of fertilization in plants

sperm fertilizes egg

5th step of fertilization in plants

zygote forms--> has genetic info from both parents

6th step of fertilization in plants

zygote undergoes several divisions

7th step of fertilization in plants

becomes multicellular embryo containing a mini leaf, root, and stem--> sheltered inside a seed

Embryo

future plant containing a mini leaf, root, stem

Seed coat

hard outer coating protects embryo

cotyledon

structure which provides nutrients to the embryo until germination

when will a seed finally germinate

when conditions are favourable

self pollination

pollen lands on the stigma of the same plant

self fertilization

pollen fertilizes the ovules of the same plant

cross pollination (goal)

pollen lands on the stigma of a different plant

cross-fertlization (goal)

pollen fertlizes the ovules of a different plant

SEXUAL REPRODUCTION IN ANIMALS

continue...

first step of fertilization in animals

occurs when both gametes, the sperm cell from the male and the egg cell from the female, combine -->this process is called fertilization.

step 2 of

zygote is formed

process (one step)

fertilization only takes place if the gametes are at the same place at the same time.

step 3 of Reproduction in animals

zygote divides rapidly

Step 4 of Reproduction in animals

forms multicellular embryo

why must gametes, zygotes, and embryos live in a liquid environment

- gametes are delicate and dry quickly

-fertilization must occur in water or internal liquid environment

-let the sperm swim

-protect embryo till it's mature

-higher success rates.

Bacterial Conjugation

-transfer of genetic material from one bacterium to another.

-takes place through a structure called pilus

-many species of bacteria conjugate(but not all)

is bacterial conjugation a method of sexual reproduction?

No - they do not form a zygote