Ans.
Gametophyte shows haploid, gamete-forming stage of plant's life cycle, while sporophyte shows diploid, spore-forming stage of plant's life cycle. In green algae, gametophytes and sporophytes are isomorphic (indistinguishable). In bryophytes, such as mosses, gametophyte shows dominant stage as it is most visible stage in their life-cycle. In vascular plants, such as ferns and seed plants, sporophytes show dominant stage.
Thus, 'seed plants show briefest gametophyte stage' and 'mosses show longest gametophyte stage.'
Answer:
1. First calculate the distance of the map for trace (eg) and spastic mutation (sps); Recombinant frequency:
vg + sps + vg sps + = 99 + 97 = 196
we are going to divide 196 by 650 (total descendants) = 0.3.
in the next step we are going to calculate the recombinant frequency 0.3 * 100 = 30 mu or cM or 30%
this shows that there is an association between vestige (eg) and spastic mutation (sps) since the recombinant frequency is less than 50%.
The squareness test is not valid because the combining frequency is far from 50%.
2. Results:
1. Genes are linked.
3. The test rejected the independent assortment law because it is not true that there is a 1: 1: 1: 1 relationship between descendants
The chloroplasts had inner membrane
Explanation:
The primitive photoautotrophs utilized hydrogen sulphide as the electron donor to perform photosynthesis for energy production.
Later upon understanding the endosymbiotic relationship of cyanobacteria which resided in the mitochondria of a eukaryotic host cell, the use of chloroplasts for photosynthesis was understood.
Generations after generations led to the development of chloroplasts by the cyanobacteria due to this symbiotic relationships which developed into the chloroplasts.
The unique presence of the inner membrane and its components like the stroma, thyllakoids helped the organism to utilize water as the electron donor for photosynthesis like the present day eukaryotes. This is the main reason why cyanobacteria is considered as the ancestor for eukaryotes.
Answer:
True
Explanation:
Sensory neurons are the neurons present in the nerves which can convert the external stimuli into an electrical signal and can transmit the signals from the organs to the central nervous system.
The structure of sensory neuron in pseudounipolar that is at one end it has dendrites and another end transmits the signals to the CNS.
The cell bodies (nucleus) of these sensory neurons are located in the structures called ganglia located outside the CNS.
Thus, True is the correct answer.
Answer:
D. Plasmids are nucleic acids which can pass on traits
Explanation:
A Nucleic acid is one of the four biomolecule polymers in living systems. It is made up of monomeric units called Nucleotides. RNA and DNA are the two nucleic acids in existence and they function in storage and expression of genetic information.
According to the question, a colony of bacteria that can break plastics were mixed with the colony that can't break plastics. The two different colonies engage plamids, which conferred the ability to break plastics to some of the colonies that previously couldn't. This tells us that the ability to break plastics in the certain bacteria colony is GENETIC.
If the trait is genetic, the plasmid must be a nucleic acid because of the ability to genetically pass on traits. Note that, a plasmid is an extra-chromosomal DNA (nucleic acid) capable of replicating on its own. Hence, plasmids are nucleic acids which can pass on traits.
