You do a serial dilution in the same manner as the one in the video. A plate with a sample volume of 10-6 mL produced 43 colonies. What was the original cell density (CFU)?
Answer: 43 x 10^6 CFU.
Explanation:
Plate count is a method used to determine the number of viable microorganisms in a sample. When the bacterial concentration is high, serial dilutions are carried out in a 1:10 sequence. Then, the dilutions are successive dilutions keeping the dilution factor constant at each step. Small aliquots of these dilutions are seeded in medium contained in a Petri dish where the bacteria grow forming colonies. Then the plates are incubated and colonies develop both within the agar and on the surface.
If the concentration of the seeded aliquot is too high, the bacteria will grow too much and it will not be possible to distinguish the colonies. However, if the concentration is very low, the number of colony forming units (CFU) may be very low and thus can be counted.
Colony forming units are calculated:
CFU = Number of colonies / (volume seeded on the plate * dilution).
The dilution is 10^-6, the number of colonies counted is 43, and usually the volume plated is 0.1 mL, so we replace that in the equation:
CFU= 43 / (0.1 mL * 10^-6)
CFU= 43000000 = 43 x 10^6
HELP ME PLEASE ILL GIVE BRAINLY IF U GET IT RIGHT PLEASE!!!!
Answer:
the right answer is option Bdefine and understand the following terms:(1)Phylum (2)Class (3)Family (4)Order (5)Genus
Explanation:
phyllum: group group of related classes
classes: group of related order
family: a group of related genera (genus)
order: group of related families
genus: group of related species
Answer:
(i) Phylum
The phylum is second highest unit of classification after Kingdom. It includes one or more related classes of animals. In plants, instead of phylum, the term ‘division’ is used.
(ii) Class
The class is a taxonomic group consisting of one or more related orders. For example, the class, Mammalia, includes many orders like Primata (Man), Carnivora (tiger) etc.
(iii) Family
Family is a taxonomic group containing one or more related genera, eg., Family hominidae contains apes, monkeys and man. In plants, families are categorized on the basis of vegetative and reproductive features.
(iv) Order
Order is a taxonomic group containing one or more families. For example, the order, carnivora, includes many families.
(v) Genus
Genus is a taxonomic group including closely related species. For example, the genus, Solanum, includes many species such as nigrum, melongena, tuberosum, etc.
I hope it's helpful!
Protein are digested and transported by fellow protein. Give vivid examples to support the statement
Answer and Explanation:
The transport and digestion of proteins is done by other proteins called enzymes. An example of this occurs in the biochemical digestion of proteins, where the enzyme pepsin promotes digestion, the breakdown of proteins into smaller pieces, through hydrolysis which is the breakdown of molecules with the use of water. These pieces of the protein are transported to the duodenum where they are digested again by the enzyme enterokinase.
Which scenario would most likely result in cooperative hunting? Finches eat grass seeds, but grass seeds are not found in an area during winter months. A shark eats a certain kind of fish, and the fish swim together when the shark comes close. Wolves eat rabbits, and the number of rabbits in an area is low. Lions eat zebra, and there are a lot of zebra and lions living in an area.
How could the extinction of plants have caused the extinction of some animals?
How does the size of the soil particles impact
the soil's permeability (movement of water)?
Answer:
Water moves by gravity into the open pore spaces in the soil, and the size of the soil particles and their spacing determines how much water can flow in. Wide pore spacing at the soil surface increases the rate of water infiltration, so coarse soils have a higher infiltration rate than fine soils.
How does soil particle size affect permeability?
But permeability is a different thing. It increases as particle size increases. By definition, permeability is a MEASURE OF EASE with which fluids will flow though a porous rock, soil or sediment. ... That means capillarity increase as particle sizes decreases.
What steps are usually included in the scientific method
Answer:
1. make an observation 2. ask a question based on your observation. 3. form a hypothesis/ make a prediction 4. do a test or experimentation 5. analyze data 6. form a conclusion
Explanation:
You only have to answer the first question. I will give brainliest to the best answer.
Answer:
The mushroom is composed of two parts, the above ground part, and the underground part. Each part has its unique function and purpose in the life cycle of a mushroom.
Spores
It is usually released into the air and falls on the ground to start the life cycle of the mushroom. Seeds that acts as the mushrooms reproductive system.
Stem
A soft branch is supporting the mushroom’s cap.
Gill
Located under the cap, it produces the spore of the mushroom.
Mycelium
This part of the mushroom serves as the breeding ground of smaller mushrooms to grow.
Hypha
The microscopic filament that draws water and the organic matter necessary for mushroom development.
Volva
The remnant of a membrane that completely covers the immature mushroom.
Ring
A covering located under the cap surrounding the stem.
Cap
The upper part of the mushroom that protects the gills. It usually resembles a headdress, hence its name.
Hope it helps!!!
Tides are caused by gravity of the__
1. Earth and sun
2.earth and moon
3.moon and stars
4.sun and moon
Answer:
the answer to your question is number 2
Im stuck in this question if you know please comment
Answer:
C
Explanation:
meiosis increases the genetic variability due to mixing of genetic material between chromosomes.
it produces genetic variation by a process known as recombination.
describe how acid precipitation affects ecosystems
will give brain crown thingy
Answer: Acid rain makes such waters more acidic, which results in more aluminum absorption from soil, which is carried into lakes and streams. Trees' leaves and needles are also harmed by acids... They are most clearly seen in aquatic environments, such as streams, lakes, and marshes where it can be harmful to fish and other wildlife.
Explanation: YW <3
discuss how classification system have undergone
Answer:
The classification systems have undergone several changes with time. The first attempt of classification was made by Aristotle. He classified plants as herbs, shrubs, and trees. Animals, on the other hand, were classified on the basis of presence or absence of red blood cells.
I hope it's helpful!
When do populations increase?
Answer:
c
Explanation:
i have seen this before and i got it correct i dont know if it works with you?
in which Domain & Kingdom would scientists classify an organism, whose cells contain a nucleus, has cell walls made of chitin, and does not have chloroplasts?
Answer:
The correct answer is -
Domain: eukarya
kingdom: fungi
Explanation:
A cell with a nucleus and cell wall made up of the chitin and does not have chloroplast, are all the characteristic features of an organism of kingdom fungi which is a group of eukaryotic organisms.
The cells with the nucleus are grouped in the domain eukarya while the prokaryotic organism does not carry a nucleus in their cell and divided into Archaea and bacteria. The chitinous cell wall without any chloroplast in the cell is one of determining features of the fungi kingdom.
What are the 4 steps of Natural Selection?
Answer:
Variation. Organisms (within populations) exhibit individual variation in appearance and behavior. ...
Inheritance. Some traits are consistently passed on from parent to offspring. ...
High rate of population growth. ...
Differential survival and reproduction.
Explanation:
The appendix, an extension of the large intestine appears, although this is debated, to have little
function in humans. What is the appendix an example of in terms of evidence for evolution?
Answer: Vestigial organ
Explanation:
Vestigial organs are those organs which were functional in ancestral organisms belonging to the same species but due to the course of evolution of body forms they become non-functional. They can be found in the body either in the same form as used to appear in the ancestors or in rudimentary or degenerated forms.
The human appendix is one of the examples of vestigial organs. It looks like a narrow tube which forms a link with a colon of the large intestine. It was functional in human herbivorous ancestors as it used to help in digestion of variety of vegetables and other plant products. The change of diet along with due course of evolution caused the appendix to become useless. But the appendix physical form remained the same in humans.
List 5 ways that phosphorous is essential to plants & animal life on Earth.
Answer:
El fósforo (P) es esencial en todas las formas de vida conocidas, dado que constituye un elemento clave en muchos procesos fisiológicos y bioquímicos. Se trata de un componente presente en todas las células de todos los organismos vivos. El fósforo aparece en estructuras complejas de ADN y ARN que, al contener y codificar la información genética, controlan todos los procesos biológicos en las plantas. Además, el fósforo es un componente fundamental del sistema de transporte de energía en todas las células.
El fósforo no aparece aislado en la naturaleza, sino que se encuentra siempre combinado con otros elementos con los que forma los fosfatos que pueden ser muy complejos y presentarse bajo distintas formas en los suelos, el agua, las plantas, los animales y el hombre. Por tanto, se utilizará la palabra “fósforo” de forma genérica en lugar de identificar el fosfato concreto, aunque en la mayoría de los casos, se ofrecerán valores numéricos como P2O5 .
Hasta una época relativamente reciente, el crecimiento de las plantas y de los animales, y por extensión, la productividad de la agricultura, se veían limitados por la falta de fósforo, ya que anualmente solo se disponía de unas pequeñas cantidades de las rocas y de los minerales del suelo gracias a la acción erosiva de los elementos. Cuando los agricultores comenzaron a utilizar fertilizantes en el siglo XIX, los niveles de fósforo disponible para las plantas en muchos suelos eran todavía muy bajos. Por eso, hasta que no se comenzó a aplicar fósforo, la respuesta a otros nutrientes, especialmente al nitrógeno, era muy pequeña, es decir, que el fósforo era el nutriente limitante del crecimiento de las cosechas.
El fósforo desempeña un papel fundamental en la fotosíntesis, proceso por el que las plantas absorben la energía del sol para sintetizar moléculas de carbohidratos, es decir, de azúcares, que son transportados a los órganos de almacenamiento de las plantas. Este proceso es esencial para todas las formas de vida y constituye el primer paso en la cadena para producir alimentos, piensos y fibras.
Las raíces de las plantas absorben el fósforo del agua presente en el suelo y que se denomina solución acuosa del suelo.
Sin embargo, los compuestos de fósforo no son muy solubles y, como consecuencia, la cantidad de fósforo que la planta puede tomar de la solución acuosa del suelo tiende a ser mucho menor de la que necesita, especialmente cuando la planta se encuentra en un periodo de fuerte crecimiento. Por eso, el fósforo de la solución acuosa del suelo debería reponerse con una frecuencia de diez veces al día en esos periodos.
En un día, una cosecha de rápido crecimiento puede absorber el equivalente a cerca de 2,5 kg de P2O5 por hectárea (una hectárea equivale a 10.000 m2 ). De esto se deduce, por tanto, que es necesario que existan reservas adecuadas de fósforo en el suelo y que esas reservas puedan estar disponibles con facilidad. La mayoría de los suelos no abonados contienen una cantidad demasiado pequeña de fósforo, fácilmente aprovechable, para dar respuesta a la gran demanda de las cosechas, en especial durante ciertos periodos del ciclo de crecimiento. De ahí, que se imponga la necesidad de aplicar fertilizantes que contengan fósforo.
La carencia de fósforo afecta no solo al crecimiento de la planta y al desarrollo y rendimiento de la cosecha, sino también a la calidad del fruto y a la formación de las semillas. Asimismo, la carencia de fósforo puede retrasar la maduración de las cosechas, con lo que se retrasa la recolección y se pone en riesgo la calidad del producto.
Explanation:
What is a main difference between Mercury and Neptune?
Mercury is an inner planet with a thicker atmosphere and a longer year than Neptune.
Mercury is an inner planet with a thinner atmosphere and a shorter year than Neptune.
Neptune is an inner planet with a thicker atmosphere and a shorter year than Mercury.
Neptune is an outer planet with a thinner atmosphere and a shorter year than Mercury.
Answer:
B because Mercury's orbit is 88 days and Neptune's is 164 earth years
Mercury is an inner planet with a thinner atmosphere and a shorter year than Neptune.
What is Mercury and Neptune?
Since 2011, Neptune has spent 12 years in the sign of Pisces, which it rules and enjoys being in. Mercury spends just 15 to 60 days in each sign of the zodiac, but because of the Mercury retrograde, they come together and hang out for a while.
This is incredibly uncommon. It may be said that Mercury, the hare, is enjoying a Long sleep with Neptune in a dreamy fog and has forgotten his responsibilities as a courier around the Earth.
When Mercury conjoined the Sun on March 14 at 24 degrees Pisces and then today, on March 25, when Mercury conjoined Neptune at 16 degrees Pisces, this was notably felt.
Therefore, Mercury is an inner planet with a thinner atmosphere and a shorter year than Neptune.
To learn more about Mercury, refer to the link:
https://brainly.com/question/4025230
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list and describe three methods of keeping a gap between the birth of two children.
class 10 biology btw
Answer:
either a barrier or chemical method can be used
i.e, is de usage pills or copper-t , condom in males .. etc ..... ( correct me if i m wrong ) ....
Write a Haiku about science please
Light and energy,
Electricity abound,
Generating life.
WILL GIVE BRAINLIEST!!
A magnetic globe is being held down on a base. When released, the globe rises above the base and eventually comes to rest floating above the base.
In which position shown does the globe have the greatest magnetic potential energy?
Answer:
Position 1 as the magnetic potential energy is waiting to be released when the hand moves.
Explanation:
reproducing a sexuality in sexuality will likely use what type of reproduction when the environment is experiencing change asexual be sexual?
Answer:
Asexual
Explanation:
When there is a constant unbalanced force applied in the opposite direction as the motion, speed will ___________________ and acceleration will ________________________.
Answer:
When there is a constant unbalanced force applied in the opposite direction as the motion, speed will decrease and acceleration will increase.
Explanation:
An opposing force should slow something down, decreasing the speed, and acceleration is just change in speed or direction.
Have a great day!
1.
Young hermit crabs pick up sea anemones which live on their shells. The stingy tentacles of the anemone keep fish from eating the hermit crab, and the sea anemone is able to eat leftover food from the hermit
crab. Which best describes the relationship between the sea anemone and the hermit crab?
A commensalism
B. O mutualism
c. parasitism
DO predation
Answer:
mutualism.
Explanation:
Mutualism can be defined as an symbiotic relationship or interaction between two or more living organisms of different species that typically involves each organism benefiting positively. Therefore, mutualism influences the survival and reproduction of living organisms in their habitats.
In this scenario, young hermit crabs pick up sea anemones which live on their shells. The stingy tentacles of the anemone keep fish from eating the hermit crab, and the sea anemone is able to eat leftover food from the hermit crab. Therefore, the relationship between the sea anemone and the hermit crab is best described as mutualism because both of them are benefiting from the interaction.
Simply stated, the sea anemone provides protection (security) from predators for the hermit crab while the hermit crab provides food for the sea anemone.
1. A group of individuals of the same species that mate and produce offspring is called a
A. gene pool.
B. niche.
C. genetic family.
D. population.
2. Any change in the genetic material of a cell is called a
A. mutation.
B. single-gene trait.
C. genotype.
D. polygenic trait.
3.In genetic terms, evolution is defined as any change in the relative frequency of
A. a single-trait gene of a population over time.
B. alleles in the gene pool of a population over time.
C. genes in a population over time.
D. phenotypes of a population over time.
A student knows the width and
length of a dresser. What else
should she measure so she can
calculate the volume?
A. Mass
B. Density
C. Height
Answer:
C. Height
Explanation:
The volume of a rectangle is Length x width x height.
The student has only measured the width and length so far, the only thing left to measure is the height.
The other answers don't make sense.
Hope this helps!!
- Kay :)
Answer:
c
Explanation:
2. (04.03 MC)
Which component is missing from the process of cellular resplration?
Glucose + Carbon Dioxide + Water + Energy
a Sunlight
b Sugar
c Oxygen
d Carbon
Answer:
c
Explanation:
Answer:
C oxygen
Explanation:
Oxygen is the missing component
hope it helps!
HELPPPPP ASAPPPPP!!!!!!
Structure that display characteristic of living organisms only within living cells
this is the answer I hope it helps u
