Answer:
Given:
Number of colonies on plate = 40
Amount of DNA used for transformation = 100ng
Volume of competent cells used = 100ul
Total volume = 1ml (1000ul)
Volume plated for growth = 200ul
The amount of cells transformed per 1 µg of DNA is called the transformation efficiency
(CFU is colony forming units) => (number of colonies on plate/ng of DNA plated) X 1000 ng/µg = CFU/µg of DNA
Amount of DNA used for plating = 100ng * (200/1000)
= 100ng * (1/5)
= 100/5 = 20ng
Efficiency calculation = 40 colonies / 20ng = 2 colonies/ng
(2 colonies/ng) * (1000 ng/µg) = 2000 CFU/ug DNA
Transformation efficiency = 2000 Transformants / ug DNA
= 2 x 10³ Transformants / ug DNA
Explanation:
Efficiency of transformation is highest in the 100 pg-1 ng range, so Low transformation efficiency could be because of high amount of DNA used for transformation.
Answer:
An embryo sac is said to form when the haploid megaspore nucleus divides. It possesses two haploid nuclei and six haploid cells which do not have cell walls.
Explanation:
The epidermis is a barrier to ultraviolet rays, blocking much of the cancer-causing radiation from reaching the nuclei of cells called keratinocytes.
<h3>
What is keratinocytes?</h3>
- Skin cells, also known as epidermal keratinocytes, are highly specialized epithelial cells created for a very specific purpose: separating the organism from its environment.
- Keratinocytes, which make up the majority of the epidermis, have a variety of functions that are crucial for skin restoration.
- They carry out the re-epithelialization process, in which keratinocytes move, multiply, and differentiate in order to reestablish the epidermal barrier.
- The majority of the epidermis's cells, known as keratinocytes, begin in the basal layer, manufacture keratin, and help to create the epidermal water barrier by producing and secreting lipids.
- A kind of stratified epithelium known as keratinized stratified squamous epithelium has many layers of squamous cells, or keratinocytes, with the superficial layer of cells being keratinized.
- The skin's epidermis is made up of this kind of epithelium.
Learn more about epidermis here:
brainly.com/question/893214
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#6 is A. They are all composed of one or more cells.
The type of deafness that is present if the bone conducted sound is heard longer than the air conducted sound is CONDUCTIVE HEARING LOSS.
Conductive hearing loss refers to the situation where there is a problem conducting sound waves anywhere along the route through the outer ear to the ear drum and the tiny bones of the middle ear.
