What have you learned while reading chapter 2: chemistry and chapter 3: Cells and how both chapters are interrelated

Answers

Answer 1

All biological things are constructed from simple units called cells. Millions of billions of cells make up the human body. They give the body structure, absorb nutrients from the diet, transform those nutrients into energy, and perform certain tasks. Furthermore, cells may replicate themselves and hold the body's genetic material.

How many different types of human cells are there?A human is made up of approximately 200 primary cell types, numbering in the trillions. A person's cells are all genetically identical (see more on genes). But the specific genes that each type of cell "turns on" influences the proteins that the cell generates. Different cell types can carry out specific functions thanks to their distinct protein repertoires. An illustration would be the transportation of oxygen by red blood cells. Invading germs are killed by white blood cells. Food-digesting chemicals are released by intestinal cells. To produce thoughts and action, nerve cells transmit chemical and electrical signals. In order to pump blood, cardiac cells also contract in unison.

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Related Questions

explain in steps how a tree trunk gets wider

Answers

Answer:

The first thing that determines the thickness of a tree trunk is the species. Some kinds of trees just naturally have a different trunk thickness than others.

The second thing might be the environment. A tree that is experiencing all factors - sun, water, soil, minerals - at an optimum level is going to grow faster, taller, stronger, and thicker than the same species in a less-optimum environment.

A third factor is time. As time passes, the tree trunk increases in diameter - thus a tree that is 50 years old will have a much thicker trunk than one that is 5 year old.

And, in case you’re wondering why or how tree trunks increase in thickness at all, there is a thin layer of cells all around the trunk of a tree, like a sheet that lives under the bark. This layer is called the cambium layer which makes new living tissue for the tree (called phloem and xylem) every year. As the year’s growth comes to an end, the living tissue dies and is pushed outward to appear as bark by the new year’s sheet of cambium cells, which is bigger than the previous year’s - hence, the increase in diameter of the tree every year.

Help me please !!!!!!!!!!!!!

Answers

Answer:

cervix

Explanation:

______ are short segments of DNA that carry the instructions to build a specific protein.
a. DNA
b.Ribosome
c. RNA
d. Genes

Answers

The answer is genes

A particular ant species has four pairs of chromosomes. Identify genetic possibilities from independent assortment of a gamete

Answers

There are "256" different genetic combinations that a gamete may make by independent assortment.

What is meant by independent assortment?

Homologous chromosomes are allocated at random to daughter cells during meiosis, while distinct chromosomes segregate apart from one another. The term for this is independent assortment. It produces gametes with distinctive chromosomal arrangements.

Calculation:

Here, the number of chromosomal pairs in the ant = 4.

Every pair of chromosomes is going to be divided into a single gamete during the gametogenesis process.

Therefore, there are 4 unpaired chromosomes in all.

Now that the gametes lack paired chromosomes, they are haploid.

Now, a gamete would only contain one of the single chromosome pairs.

Let's assume that the chromosomal gene in the cell is heterozygous.

There are thus going to be options = 2.

Therefore, their likelihood will provide possibilities =2 x 2= 4.

Then there would be 4⁴ chromosomes = 256 chromosomes.

Therefore it is concluded that the genetic possibilities from the independent assortment of a gamete are "256".

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Why are biogeochemical cycles important to
organisms?
A. Nutrients change forms as not every organism may use the
same form of a nutrient.
B. Energy is constantly recycled from space to sustain life on
Earth.
C. Energy is constantly being created to serve living organisms.

Answers

Answer:

importance of biogeochemical cycles through the ecosystem the cycle move the essitinal elements for life to sustain they are vitil as the recycle Store them to regulate the vital elements through the physical facets

WILL GIVE BRAINLIEST
Complete the sentence. Warming temperatures are increasing the occurrence of wildfires. After a fire, ______________ occurs as the habitat slowly redevelops with vegetation.

limiting phenomenon
peak phenomenon
primary succession
secondary succession

Answers

Warming temperatures are increasing the occurrence of wildfires. After a fire, primary succession occurs as the habitat slowly redevelops with vegetation

When a new piece of land is produced or is first exposed, primary succession occurs. This may occur, for instance, when lava solidifies and forms new rocks or when a glacier recedes and reveals bare rocks. In the primary succession, organisms have to start over.

The process through which plants and animals first populate a sterile area is known as primary succession. On a recently formed volcanic island, for instance, seeds carried by the wind may lodge in crevices when the rock cools.

The form of ecological succession known as primary succession occurs when organisms inhabit a region that is essentially lifeless.

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Answer:

c

Explanation:

NAD+ is a limiting factor in glycolysis. In the absence of ____________________ the conversion of (1) ____________________ to NAD+ via the ______________________________ is prevented from happening. In eukaryotes, the hydrogen atoms of the molecules mentioned in (1) are transferred to certain organic molecules in one of two methods: (2) ___________________________________ as can occur in yeast and ___________________________________ as can occur in human cells. In the process mentioned in (2), the hydrogen atoms are passed to ____________________, which is then converted to a molecule of ethanol. During this a molecule of ____________________ is oxidized to a molecule of ____________________, which allows glycolysis to continue on.

Answers

The correct options to fill in the gaps are:

ADP; NADH, and electron transport chainalcohol fermentation; lactic acid fermentation; acetaldehyde; NADH; and NAD+

What is the role of NAD+ in glycolysis?

NAD+ serves as an electron acceptor in glycolysis. It accepts two electrons to become reduced to NADH + H+.

NAD+ is a limiting factor in glycolysis. In the absence of ADP, the conversion of NADH to NAD+ via the electron transport chain is prevented from happening.

In eukaryotes, the hydrogen atoms of the molecules mentioned in are transferred to certain organic molecules in one of two methods: alcohol fermentation as can occur in yeast and lactic acid fermentation as can occur in human cells. In the process mentioned in, the hydrogen atoms are passed to acetaldehyde, which is then converted to a molecule of ethanol. During this a molecule of NADH is oxidized to a molecule of NAD+, which allows glycolysis to continue on.

In conclusion, NAD+ concentration is limiting to glycolysis.

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Which of the following is true about the Chromatids?

(a) It is a haploid chromosome

(b) It is a complete chromosome

(c) It is a duplicate chromosome

(d) It is one-half of the replicated chromosome

Answers

Answer:

(b) It is a complete chromosome

Special senses are senses that have a specialized organ associated with them. Do you think we could have more senses?

Answers

Special senses are senses that have a specialized organ associated with them. we could have more senses, with some specialized organs, like the snake, which has chemical sensors in the tongue.

What is the snake tongue sensor?

It's your main sensor. The odor molecules are captured by the tongue, sent to the inside of the mouth, where they are captured by two sensors located at the right and left ends of the palate, and the information is passed on to the brain. Through this information that is sent to the brain, the animal can distinguish whether its prey is moving to the right or to the left. Using this method, a snake can more effectively find and capture its prey.

With this information, we can conclude that we could have more senses, with some specialized organs, like the snake, which has chemical sensors in the tongue.

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If a sperm cell contains 6 chromosomesit must have come from an original parent cell that contained chromosom

Answers

Answer:12

Explanation:

What is/are the main purpose(s) of meiosis? (select all that apply)
Control metabolism
✔Halve the number of chromosomes in a cell
Generate genetic diversity
Create gametes
Synthesize energy
Organism growth
Tissue repair and maintenance

Answers

Answer:

Halve the number of chromosomes in a cell.

Create gametes.

Explanation:

Meiosis is a cell division process where the parent cell divides to give four daughter cells, each containing half the number of chromosomes. It is also called as reductional division. It is important for reproduction as meiosis is the sole way for germ cells to form sperm or eggs.

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The main purposes of Meiosis include reducing the number of chromosomes in a cell by half, generate genetic diversity, and creation of gametes. Thus, the correct options are B, C, and D.

What is Meiosis?

Meiosis is a special type of cell division which is also known as reductional division. It occurs in the germ cells in the sexually-reproducing organisms that involves the formation of the gametes, such as sperm or egg cells. Meiosis involves two rounds of division which are Meiosis I and Meiosis II, which ultimately results into formation of four daughter cells with only one copy of each chromosome.

Meiosis is an important type of cell division for three main reasons which are sexual reproduction of diploid organisms in which it produces gametes, it enables genetic diversity in sexually reproducing organisms, and it reduces the chromosome number in the daughter cells by half.

Therefore, the correct options are B, C, and D.

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PLS HELP ME WILL GIVE 100 PONITS:Explain how to compare 3 and 7 by writing the correct number or symbol in the blanks. 4 12
3 4 8 12 7 9 1
< > = 12 12 2
First, I would rewrite 3 as an equivalent fraction with a denominator of _____. 4
The equivalent fraction is ____. Then, I would compare the equivalent fraction to 7 . 12
So,
3 7
4 1

SUBJECT: science

Answers

Some examples of equivalent fractions include:

3/6 and 2/4 are both equivalents because they are equal to 1/225/50 and 50/100 are both equivalents because they are equal to 1/2, etc

What is an Equivalent Fraction?

This refers to the type of fractions that has different denominators and numerators but have the same value when broken down to the smallest terms.

Furthermore, some more examples of equivalent fractions are:

40/80 and 60/120 are both equivalents because they are equal to 1/2100/200 and 150/300 are both equivalents because they are equal to 1/2

You should also note that equivalent fractions can be found by multiplying the numerator and the denominator by the same number and you would see if your fraction is an equivalent fraction or not.

Please note that your question is unclear, so I gave you a general overview to help you get a better understanding of the concept of equivalent fractions.

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in my investigation, i saw that it can cause the growth of algal blooms which can be toxic to wild life and humans. this could also mess with marine life habitats such as coral reefs and more 

Answers

Answer:

hi I am new pls follow me

Why is water a good solvent?
A. The hydrogen bonds in water provide a network for substances to dissolve into and become trapped.
B. It is polar, and the positive and negative areas attract other polar molecules and pull them apart.
C. It is nonpolar, and the positive and negative areas attract other polar molecules and pull them apart.
D. The hydrogen bonds between water molecules are weak so they can break easily to bond to a substance that is dissolved in the water instead.

Answers

The water a good solvent because  It is polar, and the positive and negative areas attract other polar molecules and pull them apart, which means the letter B.

Why is water the universal solvent?

Water is known as the universal solvent because it dissolves almost all substances that exist in nature. There are several types of solutions made with this solvent. Substances that dissolve in water are called water-soluble.

The water is a good solvent because of its polarity and ability to form hydrogen bonds, water makes an excellent solvent, meaning that it can dissolve many different kinds of molecules.

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Which of the following is an ethical question?
A. How do we clone humans?
B. Will cloning technology be useful?
C. Do clones have the same rights as humans?
D. Can we clone humans?

Answers

C. Ethics deals with patient rights

The data in the graph are the result of a paramecium being placed in a hypertonic salt solution.

A graph entitled Paramecium Contractile Vacuole Contractions has salt concentration on the horizontal axis and contractions per minute on the vertical axis. A very low salt concentration has 30 contractions per minute, low: 22, medium: 15, high: 8, very-high: 2.

Based on the data in the graph, which would most likely happen if the paramecium were placed in distilled water?
The contractions would increase.
The contractions would decrease.
The contractions would cease altogether.
The contractions would establish dynamic equilibrium.

Answers

The contraction will increase. The first option is the correct option.

What is the contractile vacuole?

It is an organ that helps to excrete excess water from the body of some protozoans such as paramecium.

The more excess water present in the organism, the more the contractile vacuole contracts to get rid of the water.

With distilled water, more water will enter the cell and this excess water will need to be gotten rid of. Thus, the contraction rate will increase.

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Answer:

A

Explanation:

In which region would you find the BEST top soil
options: A-tropical
B- Artic
C-Temperate
D- Desert

Answers

The best topsoil will be found in the tropical region.

What are tropical regions?

They are regions of the world located within the two tropics - tropic of Capricorn and tropic of Cancer.

The region is characterized by adequate precipitation and relatively warm annual temperature. Thus, there is a high diversity of plants and animal species.

Tropical forests are known as the biodiversity hotspots of the world. This means that the soil is rich enough to support a diverse species of plants as compared to other regions of the world.

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You would find the BEST topsoil in the Temperate region

C-Temperate

How is the soil in the temperate region?

The soil of these forests is very rich in nutrients, mainly due to the natural process of leaf decomposition, which enriches the soil with nutrients. The accumulation of organic matter occurs mainly in the first horizons of the soil, which therefore have a darker color.

With this information, we can conclude that The soil of temperate region It is very rich in nutrients, mainly due to the natural process of decomposition of the leaves.

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You are reviewing a skeleton with severe trauma to the left clavicle, left scapula, and left humerus. The skull is severely fragmented as well. You notice the clavicle is separated cleanly in half mid-diaphysis. Nearby, the anterior portion the scapula has a dramatic cleft that is straight margined on its left (lateral) margin and shows jagged fracture and wastage of bone on its right (medial) margin. It progresses a full inch and a half or more downward posteriorly. The Humerus has a deep lateral transverse incision with slight chipping, deeper in the posterior aspect than the anterior. The skull is highly fragmented and bears fractures radiating from straight margin sites of trauma. The causative wounds are medium in width (3.5 mm) but very long (one runs from the most superior aspect of the right parietal, through the entirety of the left parietal at a diagonal and exits the anterior/inferior left parietal with fragmentation/wastage there and a nearby notch on the superior left zygomatic. There are three blows to this side of the skull (left), the one described is clearly the largest. Its radiating fractures end in those of the others or in bone sutures of the vault creating large triangular or irregular fragments. These blows show some wastage, biased toward the anterior aspect of each, with no evidence of crushed margins, but instead coarse striations. Which two types of trauma are indicated? What does the nature of the wounds indicate might be a likely implement? What does the order of trauma indicate about the positioning of the perpetrator and victim in this context?

Answers

The type of trauma that are indicated are both complex and  chronic traumas.

What is trauma?

Trauma can be defined as the serious event that can negatively affect the emotional, physical and mental being of an individual.

From the excerpt given, the two types of trauma represented are:

Chronic trauma: This is the type of trauma that is severe or very serious. Example is the fragmented skull and separation of the clavicle neatly in half mid-diaphysis.

Complex trauma: This occurs when there is exposure to numerous events that causes trauma.

The nature of the wound indicates that the cause would be of direct force from blows.

The positioning of the perpetrator and the victim according to the order of the trauma is that both of them where involved in a fight.

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Drag one black mouse and one white mouse in into the parent squares. What is the phenotype of all of the offspring?


A.Ff

B.Ff

C.Black

D.ff

E.white

Answers

Assuming that the allele for black is dominant over white, phenotype of the offspring will be black.

What is the phenotype of the offspring?

The phenotype of the offspring of the cross between a black mouse and a white mouse is given below:

Assuming that the parents are pure breeds and that the allele for black is dominant over white, the allele for white is w and black is W.

The offspring of the cross is as follows:

WW x ww = Ww, Ww, Ww, Ww

The phenotype of the offspring will be black.

In conclusion, the phenotype of the offspring depends in the genotype of the parents.

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If all of the large, dead trees
were removed from the
ecosystem, what would
happen to the barred owl
population in that ecosystem?
A. The barred owl population in that ecosystem would stay the same size.
B. The size of the barred owl population in that ecosystem would decrease.
C. There would be no change in the barred
owl population.
D. The amount of barred owls the ecosystem can support would increase.

Answers

The size of the barred owl population in that ecosystem would decrease.

Reduced biodiversity, or the variety and richness of various kinds of animals and plants in a given setting, is the main consequence of habitat degradation. An animal's population rapidly declines as it draws closer to extinction when it loses the habitat or natural home that it requires to survive.A proportional drop in the number of animals inhabiting a given landscape is predicted to result from habitat destruction. One might anticipate a drop in animal abundance of 50%, for instance, if 50% of a forest environment that supports a big population of an animal is destroyed.similarly, If all of the large, dead trees were removed from the ecosystem, The size of the barred owl population in that ecosystem would decrease.

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What is the best description of the word ‘Variation’ in biology?
A. Differences between individuals of a species, and between different species.
B. Change over time of a species.
C. The differences between different parts of the same organism.
D. A large group of completely different items.

Answers

A

variation, in biology, any difference between cells, individual organisms, or groups of organisms of any species caused either by genetic differences (genotypic variation) or by the effect of environmental factors on the expression of the genetic potentials (phenotypic variation).

What are the impacts of that process of production
on the environment, on society and
on individuals?

Answers

Answer:

Lack of distinctive advantage in product performance and price.

Over estimation of the target market which may result in low demand.

Inability to utilize company strength to capture profitable opportunities.

Unpredictable change in consumers preference for goods and services.

Negative Effects of Production on Environment and Society. It leads to the pollution of the environment (environmental pollution) It leads to erosion as a result of big holes created by construction industries.

Explanation:

hope this helps you, sorry if it is not what you are looking for.

Who sets the guidelines for water protection?
residents
local agencies
you
EPA

Answers

Answer:EPA

Under SDWA, EPA sets standards for drinking water quality and oversees the states, localities, and water suppliers who implement those standards.

Explanation:

Scientific question: Why does a dog circle its
bed before lying down?
Write the steps you would take to explore this
question using the scientific method.

Answers

Answer:

Explanation:

In the scientific method first of all is you need to identify the problem, the problem to your question is why does the dog circle its bed before lying down. Second is the observation to gather some data, you need to observe the dog if what could be the possibility the the dog may do that action. The third is the pre hypothesis, you need to came up with an idea why does the dog do such and action for example the needs to find a correct spot to make itself comfortable and lastly the hypothesis, this should answer to your question or your problem. So my hypothesis is that dogs are one of the animals that are those difficult to find a place to sleep and some of that kind of animals are cat, before they lay on their bed, they have to circle to find a spot that could fit its body to be more comfortable when the dog sleep.....

gamma ray
microwave
rapido wave
ray​

Answers

Answer:

radio wave

Explanation:

1km = 1000 metres, or 10³, so it must be a radio wave

what are the different types of enzymes, their importance and specific functions in the human body

Answers

Proteases, Lipases and Amylases are the different types of enzyme in the human body.

What are the different types of enzymes?

There are three main types of digestive enzymes in the human body such as Proteases, Lipases and Amylases.

Proteases is a type of enzyme that break down protein into small peptides and amino acids.

Lipases is an enzyme that break down fat into fatty acids plus a glycerol molecule.

Amylases is an enzyme that break down carbohydrates like starch into simple sugars.

So we can conclude that Proteases, Lipases and Amylases are the different types of enzyme in the human body.

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Population genetics is the study of _______.
A. how allele frequencies in a population change over time
B. populations of cells in an individual
C. the rate of population growth
D. how genes affect embryological development

Answers

According to the research, the correct option is A, population genetics is the study of how allele frequencies in a population change over time.

What is population genetics?

It studies the origin, amount and distribution of genetic variability present in populations.

It explains the variation between individuals, as well as the dynamics of alleles and genotypes within and between populations.

Therefore, we can conclude that according to the research, the correct option is A, population genetics is the study of how allele frequencies in a population change over time.

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Non-steroidal hormones can be produced by all of the following except the

pancreas
pituitary gland
hypothalamus
adrenal cortex

Answers

Answer: its b i just got done with it

Explanation:

6. What asexual reproduction process is utilized by Eubacteria?
A. binary fission
B. RNA production
C. ribosome creation
D. agamogenesis

Answers

The answers is A binary fission
It’s Binary fission

Part B: Find Credible Sources When designing a science presentation, look for credible sources. Science doesn’t show bias, but humans do. Avoid sites and articles that provide facts without citing proper scientific evidence. You must be able to identify reliable sites so that the data in your presentation is credible. Use sources that end in .gov, such as CDC.gov. These government sites are reliable sources. You can also use sites ending in .edu. They are usually trustworthy, but sometimes students, not scientists, write content for .edu websites. Always identify the source’s author before proceeding. Some .org and .com sites are credible, but it’s important to verify their authenticity. When reviewing a source, ask these questions: Who is the author? Is this person an HIV or AIDS expert? What is the document’s purpose? Does the document state facts that scientists can prove with evidence? Are there opinions in the document? How old is the document? Do other credible sources support the statements in the document? Search for credible websites and note the information they contain. Write down two sources that you will use for your presentation, and cite them using Modern Language Association (MLA) citation methods.

Answers

Authors whose work is regarded in their fields of the study write credible sources. Authors who are trustworthy and responsible will cite their sources so that you can verify the truthfulness of and support what they have written.


In the combustion process, oxygen and biomass are mixed in a hot atmosphere to produce carbon dioxide, water vapor, and heat. When sulfur dioxide and nitrogen oxides are released into the atmosphere and are carried by the wind, acid rain results. Fossil fuels differ from biomass in that they discharge carbon dioxide into the atmosphere. The approximate chemical formula for coal In terms of producing the most energy per unit of carbon dioxide released, natural gas is the best fossil fuel. Because a new crop can be planted after each harvest, biomass is a renewable resource and a low-carbon fuel. On carbon support, tungsten carbide and nickel form the catalyst. It is more plentiful, uninterrupted use is possible, and it is cleaner than fossil fuel.

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