Answer: The bacteria transformed with this particular plasmid will form white colonies on the plates containing ampicillin and Xgal.
Explanation: The lacZ gene produces an enzyme called β-galactosidase which is responsible for the breakdown of lactose into glucose and galactose. The lacZ gene is one of the three genes (the other two being lacA and lacY) of the lac operon which is responsible for the transport and mechanism of lactose in E. coli and many other bacteria.
In recombinant DNA technology, when a plasmid is to be used to transform a host cell, such markers are used to help screen the transformed cells from the ones that have not taken up the plasmid. Xgal present in the plates is an artificial substrate which is hydrolyzed by
β-galactosidase into 5-bromo-4-chloro-indoxyl which will dimerize and oxidise into 5,5'-dibromo-4,4'dichloro-indigo. This is a blue pigment which will give blue color to the bacterial cells. Introducing a DNA fragment in this lacZ gene will make it non-functional so it will not be able to produce the enzyme.
Therefore, when a bacterial cell is transformed with a plasmid containing ampicillin resistance gene and a DNA fragment introduced in the lacZ gene and then grown on plates containing ampicillin and Xgal, white colored colonies will appear. The white colonies will show the bacterial cells that have successfully taken up the plasmid with the DNA fragment incorporated in the lacZ gene as this will render the gene non-functional and will not produce β-galactosidase which will breakdown Xgal to give blue colonies. Since the plates contain ampicillin, only the bacterial cells that have been successfully transformed with the plasmid ( the ones that have the DNA fragment and the ones without it) will grow as the ampicillin resistance will give them resistance against ampicillin in the plates. The bacterial cells that have not taken up the plasmid will not be resistant to ampicillin and will not form colonies on the plate.
This is called blue-white screening which is used to identify successfully transformed host cells. A picture of this is given in the attachment, taken from the following website:
https://www.mun.ca/biology/scarr/Blue_&_White_Colonies.html
I don't understand, what is the question you're supposed to answer?
Answer:
The correct answer is - per gram, the marathon runner's muscles would contain more myoglobin than the sprinter's muscles.
Explanation:
Marathon runners have smaller leg muscles and thinner quads and calves as marathon runners require slow-twitch muscles while in sprinters the fast-twitch muscle requires. Slow-twitch muscles of marathon runners have more amount of myoglobin, per gram than fast-twitch muscles.
Myoglobin acts as local oxygen storage that provides oxygen to the muscles in case of less oxygen supply than required temporarily and a marathon race is an intense exercise or activity that requires more oxygen.
You do:
R R
R
r
Your offspring would be: RR, RR, Rr, Rr
So, about 50% of the offspring will have red flowers
Your answer is
50%
1. Answer;
It facilitates the movement of the fetus towards the pelvic girdle thus the child is born headfirst.
Explanation:
- During labor the pelvic floor facilitates movement of the fetus towards the pelvic girdle by resisting the descent of the presenting part. This makes the fetus to rotate forwards and therefore results in majority of the fetus being born headfirst.
2. Answer;
Purple pushing lead to development of pelvic floor problems.
Explanation
;
- Purple pushing involves the midwife instructing a woman to hold her breath for ten seconds while forcefully pushing down during a contraction.
- in the second stage instead of waiting for the mother to feel the instant urge of pushing which lead to development of pelvic floor problems.
3. Answer;
Exercise can help to strengthen the abdominal muscles and reduce the appearance of diastasis recti.
Explanation;
- By contracting transversal abs muscles they strengthen and pull the muscles inwards.
- The diastasis recti reduce with time due since the rectus muscles come close to each other enabling a human being to live a normal life because flexion, bending and stability becomes easy.
4. <u>Answer</u>
- Pelvic floor muscles
- Stomach muscles
- Abdominal muscles
- Perineal muscles
- Uterine muscles
<u>Explanation</u>
- Abdominal muscles are stretched to their limit by term. They greatly decrease the ability to perform strong contraction.
- Pelvic floor is vulnerable to muscular and neurological injury during labor and delivery.
- Perineal muscle tightening strengthens the pubococcygeus muscle and increases its tone.
5. Answer and explanation;
- Sports that can lead to falling down e.g. skating
- Sports that may involve altitude change
- Exercises that involve lying flat on your back
- Exercises that involve holding o breath
- Motionless standing
6. Answer
Yes
Explanation
;
- Exercise maintains physical fitness, health and wellness aiding growth to the unborn since the mother gains enough strength and energy and there is proper blood flow.
- Many pregnant women tend to gain weight which may lead to health difficulties for example struggling to breath. The pregnant lady is able to cope with labor and she is able to get back in shape after the baby is born.
7. <u>Answer</u>;
One is supposed to get up slowly and gradually to avoid dizziness.
<u>Explanation;</u>
- Dizziness happens after a tiresome activity done continuously for a period of time thus one should get up slowly and gradually to avoid other injuries like falling endangering the life of the unborn child.