Because, substances can pass through it while others can not but Oxygen, good molecules,
and waste products can only go through it.
Does the time taken to travel a set distance increase as speed increases?
This is an example of a scientific question because it can be answered through an experiment and data analysis.
Answer:
Explanation:
A cross between plants with round seeds (RR) and plants with wrinkled seeds (rr). If both parents are homozygous, having one type of gamete each, i.e. R from round seed parent and r from wrinkled seed parent (RR X rr).
R R
r Rr Rr
r Rr Rr
All the offspring of generation would be round with genetic constitution Rr. They will be heterozygous plants having two different alleles.
If both parents has heterozygous round seeds with genotype Rr. So, we have Rr × Rr. The gametes produced from each of the parents are of two types, R and r.
R r
R RR Rr
r Rr rr
The generation has a genotypic ratio of 1 RR : 2 Rr : 1 rr. The phenotypic ratio is 3 round : 1 wrinkled.
The answer is about 10,000 years ago. Hope this helps.
In the absence of glucose and in the presence of lactose, the lac repressor is bound to the allolactose, and the lac operon can start.
<h3>What is the lac operon?</h3>
A lac operon is an inducible operon that is activated in the presence of lactose in the outer surroundings of the bacteria. Operon is a series of genes present in the bacterial DNA.
When the lactose is present, the repressors move to bind the allolactose, and as a result, the RNA polymerase can access the lac operon. The repressor has more affinity for allolactose than the operator. RNA polymerase, along with cAMP and CAP proteins, initiates the transcription of lac operon. The transcript has genes for galactosidase, permease, and transacetylase.
Hence, in the absence of glucose and in the presence of lactose, the lac repressor is bound to the allolactose.
Learn more about the lac operon, here
brainly.com/question/2562849
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