Answer:
1665
Robert hooke
Answer:
In 1665, Robert Hooke looked at a piece of cork under his
microscope and called what he saw cells.
Explanation:
Robert Hooke performed several experiments on the work of the cell theory and overall was the first scientist to discover them and coin the name of cells.
Hope that this helped out! (●´ω`●)
The image here shows potential outcomes for chromosomes at a particular stage of meiosis. Which questions appropriately assess what is happening in the image. Select ALL that apply.
A) How does crossing over increase the outcome of meiosis?
B) How does fertilization increase genetic diversity in a diploid organism?
C) How does independent assortment increase genetic diversity during meiosis?
D) How many potential combinations result from chromosomes alignment during metaphase I?
E) How does chromosome methylation result in silencing specific genes during gamete formation?
According to the random arrangement of homologous chromosomes in the equatorial plane, the correct question is D) How many potential combinations result from chromosomes alignment during metaphase I?
How does the random arrangement of tetrads occur?During metaphase 1, chromosomes' homologous pairs migrate to the equatorial plane. Once there, they randomly aline facing their kinetochores to the opposite poles.
The random arrangement of tetrads is different in every cell going through the meiosis process. This is because there is no equal alinement between two cells.
When tetrads arrange in the equatorial plane, there is no predetermined order. Each homologous chromosome of each tetrad faces any of the poles and then migrates to it while separating. Each of the chromosomes has two possibilities for orientation at the plane.
When the new haploid cells are formed, the number of variations in each cell is also different and depends on the chromosomes that form that cell.
This random order in the equatorial plane is what introduces variation into the gametes.
The correct question is D) How many potential combinations result from chromosomes alignment during metaphase I?
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Answer:
C and D
Explanation:i just did the problem on USA test prep
Help is much needed please, thank you?
Answer:
I belive the answer is #3
Explanation:
An igneous rock has a coarse texture and is dark in color. How else can this rock be accurately described?
small crystals
cooled quickly
produced from magma
formed at Earth’s surface
Answer:
C. produced from magma.
D. formed at Earth’s surface
Explanation:
Earth crust refers to the outermost layer or thin shell which makes up the earth such as sedimentary, metamorphic and igneous rocks.
The Earth crust is typically made up of two (2) main types;
1. Oceanic crust: this crust has a thickness ranging from 5 km to 10 km and comprises of denser rocks such as diabase, gabbro and basalt.
2. Continental crust: this crust has a thickness ranging from 30 km to 60 km and comprises of minerals such as quartz, silicate, feldspar, aluminum and less dense rocks such as granite
An igneous rock has a coarse texture and is dark in color. Also, an igneous rock can be accurately described as being produced from magma and formed at Earth’s surface.
Answer:
Produced from magma
Explanation:
I got it right on the test hope this helps
☺️
through which plant structure does water move by capillary action?
Answer:
Xylem
Explanation:
what is a example of acceleration?
Answer:
For example, if a car turns a corner at a constant speed, it is accelerating because its direction is changing. The quicker you turn, the greater the acceleration. So there is an acceleration when velocity changes either in magnitude or in direction, or both.
Explanation:
hope this helps... (i can't see the pic...)
(─‿─)
Choc
Fill in the blanks to complete these sentences about rock characteristics.
A rock is an
of minerals.
The
of a rock is a result of its mineral composition.
Most rocks contain more than one type of
Answer and Explanation:
A rock is an made of minerals??
The forming of a rock is a result of its mineral composition??
Most rocks contain more than one type of mineral??
Answer:A rock is an made of minerals??
The forming of a rock is a result of its mineral composition
Explanation:
A newly identified virus infects a eukaryotic host cell without producing virions right away, with a long period where the host is largely unaffected by the infection. What's the best description of this virus?
A: This virus rapidly causes lysis of the host cell
B: This virus has a long period of latency
C: This virus is a bacteriophage
D: This virus can't replicate
The best description of the virus is that the virus cannot replicate. The correct option is D.
What is a virus?A virus is an infectious agent which is non-living normally, but it becomes alive when come in contact with any living cell. It causes many diseases in humans, animals, and plants.
Here, the virus is not producing virions, which means it doesn't cause lysis. It doesn't affect the host, so do not have a long period of latency, and is not a bacteriophage, so the virus is not replicating.
Thus, option D: This virus can't replicate is correct.
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The maximum number of individuals that a population
can support and sustain is known as ?
A Carrying capacity
B Limiting Factor
C Migration
D Density
Answer:
the answer would be migration
4. What is a chromosome?
Some argue that solar power should be the main energy source for the United States. Which argument could be used against this idea? A. It contributes to global warming. B. It can only be produced in sunny areas. C. It is a nonrenewable resource. D. It releases greenhouse gases.
Answer:
A. It contributes to global warming
Explanation:
Solar power is the power of the future and is an essential nonrenewable source of energy for man. Solar power is driven by the incoming solar energy in the form of solar rays. Solar power is eco-friendly and doe not cause any harm can be sued in the summer season and has ample scope for greenhouse gases. As per the statement, the solar power should be used as the main energy source in U.S can be contradicted by saying it contributes to global warming.I will mark brainiest for correct answer
A pelican has a dip netting beak. How does it eat?
A. It traps fish between its upper and lower mandible much like a scissor,
B. It takes a big gulp of water with fish and filters the water off of the fish before swallowing,
C. It opens holes in trees and eats insects beneath the surface of the wood,
D. It burrows in the mud to find insects and other small invertebrates beneath the surface
Answer:
b is correct
Explanation:
Answer:
b they scoop them and then drain the water a swallow all remaining animals
Which nucleic acid serves as a strand for protein synthesis?
a. tRNA
b. ribosome
c.mRNA
d.dATP
Answer:
c.mRNA...............
The kidneys and sweat glands both work to prevent excesses of
a) either uric acid or urine in the body.
b)either water or salt in the body.
c)either carbon dioxide or oxygen in the body.
d) either feces or pH levels in the body.
Answer: The kidneys and sweat glands both work to prevent excesses of either water or salt in the body
Explanation:
The kidneys and sweat glands both work to prevent excesses of either water or salt in the body. Thus, the correct option is B.
What is function of kidney and sweat glands?Both the kidneys and the sweat glands excrete nitrogenous wastes, water and electrolytes. They are also involved in maintaining acid-base balance.
kidney is the organelle present below the abdomen whereas the sweat gland is exocrine glands that release the substances into a duct or opening to the inside or outside of the body.
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At what light intensity do both sun plants and shade plants have the same rate of
photosynthesis?
Answer:
The rate of photosynthesis is at a maximum over a narrow range of light intensities.
Explanation:
Light provides the energy required to drive the process of photosynthesis. Starting from a low light intensity, the rate of photosynthesis increases as intensity increases. Hopefully helps ig
Pearl the whale had a horrible accident at cheerleading practice and needed a blood transfusion. So she needed to find out her possible blood type. Her dad, Mr. Krabbs is heterozygous for blood type A and her mom is heterozygous for blood type B. Make a Punnett square to show Pearl’s possible blood type(s). Mr. Krabbs genotype: ________ Mrs. Krabbs genotype: ________ What is the possibility of Pearl having blood type O? ____ What is the possibility of Pearl having blood type AB? ____ What is the possibility of Pearl having blood type A? ____ What is the possibility of Pearl having blood type B? ____ - Is this scenario an example or incomplete dominance or codominance? Explain. - How can some people receive O-type blood which is recessive?
Answer:
Mr Krabs genotype: A0
Mrs K= B0
Possible genotypes: AB, B0, A0, 00
The possibility that pearl has blood type O is 25%, type A 25%, type B 25%
this scenario is an example of codominance
The diagram below shows a ciliated cell from the lining of the airway.
Which of the following states its function?Required to answer. Single choice.
(1 Point)
A)it is the place where diffusion of gases take place
B)it moves mucus and sweeps dust from lungs
C)it secretes trypsin
Pls tell meeee quickkk
Answer:
the answer is a. any ciliated cell in lungs catches bacteria & debris from lungs causing cough, difficulty breathing, etc.
can develop into asthma, infection of pleura, and bronchitis...
The amount of energy at each trophic level in an ecosystem decreases as it moves through the ecosystem. Typically, only about 10 percent of the energy at one trophic level is transferred to the next level. The remaining energy is lost through metabolic processes as heat.
Suppose that, in the ecosystem modeled above, 150,000 kcal (kilocalories) of energy are contained within green plants. Assuming that the amount of energy transferred from one trophic level to the next is exactly 10 percent, determine the following amounts of energy in the ecosystem.
Answer:
Explanation:
Energy transferred to next trophic level=10%×150,000kcal
=10/100×150,000
=15,000kcal
The amount of the energy in the ecosystem should be considered as the 15,000kcal.
Calculation of the amount of energy:Since there is 150,000 kcal (kilocalories) of energy are contained within green plants.
And, 10 percent of the energy at one trophic level is transferred to the next level.
So here the amount of energy be like
= 10% of 150,000
= 15,000 kcal
Hence, The amount of the energy in the ecosystem should be considered as the 15,000kcal.
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Someone please help ASAPPPP
Answer:
(its C)
if its right tell me!
practice: density calculations
Which RNA molecule is matched with its correct function?
Answer:
Which class of RNA is correctly paired with its function? Transfer RNA (tRNA): attaches to an amino acid. What is the difference between the template strand and the nontemplate strand? The template strand is the DNA strand that is transcribed into an RNA molecule, whereas the nontemplate strand is not transcribed
1.) A person walks 12.5 km in 1.9 h. What is the person's
average velocity in km/h and m/s?
Answer:
1. 6.56 km/hr
2. 1.83 m/s
Explanation:
The average velocity/speed can be calculated using the formula;
Average speed/velocity = distance/time
According to the information provided in the question, distance = 12.5km, time = 1.9h
Average velocity in km/hr = 12.5/1.9
= 6.578
= 6.56km/hr
However, in order to calculate the average speed in m/s, we have to convert distance in km to m, and time in hour to seconds.
1km = 1000m
12.5km = 12.5 × 1000
= 12500m
1 hour = 3600seconds
1.9hours = 1.9 × 3600
= 6840seconds
Average velocity = 12500/6840
= 1.827
= 1.83m/s
1 pe If a fox has 15 pairs of chromosomes in it's lung cell , how many total chromosomes are in it's eye cell? (type the number only) * Your answer
El mundo comas en el oya, pedthon el numbaras.
What is one characteristic that a star’s spectrum can reveal?
A.
its direction
B.
its temperature
C.
when it was formed
D.
its constellation
Answer:
B. Temperature
When you flex your knee, where are the fulcrum and the load? Where is the muscle that provides the effort located?
Explanation:
the fulcrum is the knee joint
the load is probably the radius and ulna with the muscle on it
while the effort could be tendons and the muscle on the femur
What is the primary mechanism associated with the role of fluoride in prevention of dental caries? a. Fluoride increases calcium absorption, which increases crystal formation of teeth b. Fluoride increases salivation which aids in the removal of bacteria and the foods needed to sustain bacterial growth c. Decay is reduced due to the inhibitory effects of fluoride on growth of bacteria on the teeth d. Fluoride becomes incorporated into the crystalline structure of teeth, making them less susceptible to decay e. Decay is inhibited due to neutralization of organic acids produced by bacteria on the teeth
Answer:
d. Fluoride becomes incorporated into the crystalline structure of teeth, making them less susceptible to decay
Explanation:
Dental caries results when cariogenic (caries-causing) bacteria metabolize carbohydrates or sugars present in the mouth for their energy needs, producing organic acids as byproducts, thus lowering the pH of the plaque biofilm.
The hydroxyapatite of tooth enamel is composed mainly of phosphate ions (PO₄³⁻) and calcium ions (Ca⁺). Under normal conditions, there is a stable equilibrium between the calcium and phosphate ions in saliva and the crystalline hydroxyapatite. At low pH (acidic conditions), there is a shift in equilibrium resulting in the dissolution of hydroxyapatite from tooth enamel, a process known as demineralization. A reverse process called remineralization (the process of incorporation of minerals in tooth enamel) occurs when the saliva, acting as a buffer elevates pH. When equilibrium is shifted to favor continued demineralization, dental caries results.
However, when fluoride is present in saliva, fluorapatite, rather than hydroxyapatite, forms during the remineralization process as fluoride ions replace hydroxyl groups in the formation of the apatite crystal lattice.
Fluorapatite is less soluble than hydroxyapatite making it more resistant to demineralization, even under conditions of low pH. Thus, fluoride acts as an effective anticaries agent.
Which type of law is used to discipline members of the armed services?
Answer: D
Explanation: because they are in the military and that’s the only law I would recommend if someone needed discipline in the military
why is reproductive isolation insufficient to define a species?
A. This definition overlooks artificial preproduction, such as in zoos
B. Reproductive isolation doesn't take outgroups into account
C. This definition excludes organisms that reproduce asexually
D. Reproductive isolation can be accomplished in a variety of ways
The correct option is (c) This definition excludes organisms that reproduce asexually.
Asexual reproduction is also possible in bacteria, yeast, fungi, plants, and other organisms. Most frequently, yeast proliferate by budding. Plants and fungi both use spores for asexual reproduction. Additionally, plants are capable of reproducing asexually by vegetative propagation.Numerous eukaryotic creatures, such as plants, animals, and fungus, are also capable of asexual reproduction. Parthenogenesis, the most prevalent type of asexual reproduction in vertebrates, is frequently employed as an alternative to sexual reproduction when sexual reproduction isn't an option.What are the 4 types of asexual reproduction?Asexual reproduction includes fission, budding, fragmentation, and parthenogenesis, while sexual reproduction is achieved through the combination of reproductive cells from two individuals.
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Which of the following molecules comes from the food we eat and is needed for energy?
A) amino acids
B) glucose
C) oxygen
D) protein
E) fiber
PLS ANSWER QUICK! I WILL GIVE POINTS, ITS JUST A YES OR NO QUESTION!
In two or more complete sentences, describe a scenario where human activities are related to an increase or decrease in biodiversity in an ecosystem.
I WAS THINKING OF WRITING ABOUT THE DEFORESTATION IN THE AMAZON, HOW THAT CAN KILL THE ANIMALS. OBV IF THE ANIMALS ARE DEAD THAT CAUSES A DECREASE IN BIODIVERSITY. IS THIS RIGHT?
Answer:
Yes?
Explanation:
Why are most systems in the human body negative feedback systems?
Most systems in the human body are negative feedback systems because negative feedback systems allow humans to regulate and stabilize their systems, which is the first option as a negative feedback system regulates the body's functioning.
What is the negative feedback system?Negative feedback is a regulatory mechanism in which a change in a physiological variable triggers a response that opposes the initial change, for example, in the regulation of body temperature, when the body becomes too hot, thermoreceptors in the skin and other tissues detect the change in temperature and send signals to the hypothalamus, which acts as the body's thermostat and as a feedback mechanism, hypothalamus triggers responses that cool the body, such as vasodilation to increase blood flow to the skin, sweating to release heat, etc.
Hence, most systems in the human body are negative feedback systems because negative feedback systems allow humans to regulate and stabilize their systems, which is the first option.
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