What is the comparison between sexual and asexual reproduction?
Sexual requires a male and female of the species, each contributing DNA to the offspring. Asexual, usually simple organisms, can reproduce by dividing and replicating themselves.
What are the different types of asexual reproduction and how do they work?
Asexual reproduction is of six typesThe types are1.Budding2.Fragmentation3.Spore Formation4.Vegetative propagation5.Binary Fission6.RegenerationBudding:- Budding is a type of reproduction which takes in yeasts which is a single celled organism. It sends out one or more tiny outgrowths which are known as buds. The buds may stockpile to form chains of buds. The nucleus of the yeast cell is divided and is passed on to each of the buds. The buds upon fully developing are cut of from the yeast cell and become new individual organisms,Fragmentation:- Fragmentation takes place in filamentous algae such as the spirogyra. The algae is divided into two parts by the running water, then the new part develops into a new organism.Spore Formation:- Spores are asexual reproductive organs found in plants such as ferns or moss. The spore settles over a hyphae(a thread like structure) then creates new spores which are protected by a thick covering known as the sporangium which is borne on a stalk known as the sporangiophore. The spores can be released at any time and can be carried anywhere. Upon finding suitable conditions they may germinate.Vegetative propagation:- Vegetative propagation takes place in advanced plants through their vegetative organs. The flower is not involved. Some plants like potato store food to survive through adverse conditions. There are various examples of vegetative propagation taking place in plants some of them are :- Root Tuber,Rhizome,Tuber,Runner,Foliar Buds etc.Binary Fission:- In Binary Fission the organism’s Dna is duplicated . it then divides in two(via cytokinesis) with each copy receiving one copy of the Dna. Amoeba reproduces by this process.Regeneration:- In this process , a broken part of the organism(which broke accidentally) develops into a complete organism.Planaria reproduces by this processHope this helps you
Are true-breeding varieties heterozygous or homozygous?
Generally homozygous... if they "breed true" the F1 generation has the same genetic makeup as the P generation. Do a punnett square of AA x AA, AA x Aa, Aa x Aa and aa x aa and see which crosses give offspring that are always like the parents. ------- There is a notable exception in plants -- don't bother with this unless you're in a college level botany or agronomy class: The "generally homozygous" answer breaks down, however, when you've got plants that are apomictic -- they produce seeds that are not derived from egg and sperm, but from vegetative cells of the seed parent. Dandelion is an example of this -- the plants go through what looks like sexual reproduction, but the embryos are actually formed from maternal cells, and thus it doesn't matter if the plant is heterozygous or homozygous -- it's a genetic copy of the parent. Apomixis is a fairly rare condition, but can be important evolutionarily.