Flatworms
James H. Thorp, D. Christopher Rogers, in Field Guide to Freshwater Invertebrates of North America, 2011
B Reproduction and Life History
Some flatworms, especially those living in temporary aquatic habitats, reproduce only once per year (univoltine), while other species are multivoltine, with the number of generations depending on environmental favorability. Most flatworms reproduce sexually, and almost all species are hermaphroditic. Although gamete exchange is most common, self-fertilization is possible in some species. Eggs are laid singly on a hard substrate, are grouped into clusters (sometimes stalked), or are placed in cocoons. Miniature flatworms emerge from eggs which have been attached to the substrate. These usually develop directly (without intermediate larval stages) into adults and differ only in size and presence of reproductive organs. A few species are ovoviviparous (young brooded inside parent) or have a distinct larval stage. Asexual reproduction occurs seasonally in many taxa and is the only form of reproduction in a few species. This form of reproduction involves differentiation of the adult body into distinct units (zooids) followed by separation into small flatworms via transverse division of the adult body. This process is aided by the remarkable regenerative abilities of flatworms.
Under demanding environmental conditions, flatworms produce resistant eggs able to survive desiccation of the surrounding environment or the animal may enter diapause (a very low metabolic state) and encyst as a whole animal or fragment of the adult.
Sexually reproducing flatworms can live from a few weeks to a few months (not counting periods of encystment), while the life span of asexual species is theoretically indefinite.
You have planted corn in a field with clay soil. The field is predominantly flat with a slight slope at one end where a creek borders the field. You notice that germination and growth is slowest in the flattest portion of the field. Conversely, you also notice that you received good germination and rapid growth on the slight hill which meets the creek. You wonder why there should be differences in growth and germination in different parts of the field. Is it due to the extra water near the creek? Is there something different about the soil in that portion of the field, or is it due to the difference in slope (north, south, east, and west). 1. What is your hypothesis for this problem? 2. Design an experiment to test the hypothesis you have written (make sure you include a procedure [step by step list of what you will do], an IV, a DV, treatments, trials, and constants).
Hypothesis: The soil in the flat part of the field has less fertility than the soil on the small hill.
Experiment:
The experiment will be carried out in a greenhouse, to promote a controlled environment and equal to all plants used in the treatment.
In this experiment, the influence of the difference in fertility of the soil samples, in the flat part of the land and in the most inclined part, in the germination and growth of corn plants will be tested.
Corn seeds of the same species will be selected. All seeds will be sanitized and will go through the same dormancy breaking process, so that all of them have their germination stimulated.
Vessels with a capacity of 30 kilos will be caught. These pots will be cleaned, sterilized and filled with the same amount of soil collected in the field and with two corn seeds. It will be used 10 pots with soil that was collected in the flat part of the land, 10 pots with soil from the sloping part of the land and 10 pots with fertilized substrate containing high levels of fertility.
The pots will be placed in a greenhouse and will be irrigated with distilled water, to avoid contamination by possible substances in the water.
The pots will remain in the greenhouse for 100 days, where the behavior of seeds and plants in each of them will be observed and noted. After this period, a comparison will be made between the vessels of each treatment, assessing the differences between them and reaching the conclusion whether the hypothesis is true or false.
Hypothesis: The soil in the flat part of the field has less fertility than the soil on the small hill.
Experiment:
The experiment will be carried out in a greenhouse , to promote a controlled environment and equal to all plants used in the treatment.
Procedure:
In this experiment, the influence of the difference in fertility of the soil samples, in the flat part of the land and in the most inclined part, in the germination and growth of corn plants will be tested.Corn seeds of the same species will be selected. We will choose containers with more capacity. These pots will be cleaned, sterilized and filled with the same amount of soil collected in the field and with two corn seeds. It will be used 10 pots with soil that was collected in the flat part of the land, 10 pots with soil from the sloping part of the land and 10 pots with fertilized substrate containing high levels of fertility.These pots will then be placed in a greenhouse and will be irrigated with distilled water, to avoid contamination by possible substances in the water.The pots will remain in the greenhouse for 100 days, where the behavior of seeds and plants in each of them will be observed and noted.Thus after this experiment we can conclude that whether hypothesis matches with the experiment.
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11.
Which of these best represents a fatty-acid molecule?
H
H-C-OH
U-I
H
Η Η Η Η Η Η Η Η Η
IIIIIIIII
C-c-c-c-c-c-c-c-cc-H
IIIIIII
н нннннннн
F
H
HOCH
H-C-OH
IO-U-I
IO-O-I
HN-H
Answer:
F. Is fatty acid molecule.
Explanation:
It's unsaturated fatty acid.
Fatty acid consists of a straight chain of an even number of carbon atoms, with hydrogen atoms along the length of the chain and at one end of the chain and a carboxyl group (―COOH) at the other end.
It is that carboxyl group that makes it an acid (carboxylic acid).
Which type of compounds dissolve easily in water?
A. Covalent and Nonpolar
B. Nonpolar and ionic
C. Polar and ionic
D. Polar and Nonpolar
can someone help on 31 a and b, and 32??
Answer:
the answer to 32 would b option C cellulose
Which of the following would test positively with Benedict’s reagent?
A. Corn starch polysaccharide
B. Lactose disaccharide
C. Glucose monosaccharide
D. Vegetable oil-lipid
Why does a pollutant end up multiplied as it travels up the food chain from producers to consumers?
Answer:
This is due to bio magnification.
Explanation:
When there is a gradual increase in concentration toxins(pesticides) in the tissues of organisms progressively in the food chain,the term for describing this is called -bio magnification.
The progressive multiplication in the concentration of these toxins may be due to non-biodegradable nature of the toxins,which are absorbed into the tissues of mostly the producers from the environment faster than they could metabolized by the body.
.Therefore these could not be removed by the producers, during excretion and respiration,and hence build up progressively upwards in the consumers.
A typical example is the phytoplankton which absorb toxins from sea water and accumulate this in the body.The build could not be ,metabolize by the body system,and is transferred to the zooplankton along the food chains when they feed on the phytoplanktons- this is Bio magnification.Please help me with this question!!!!!
ANSWER ASAPP
Explain molecules
Answer:
Molecules are parts of stuff all over in the air
Explanation:
describe the active site of an enzyme. why is it important?
Answer:
An active site contains a binding site that binds the substrate and orients it for
catalysis. The orientation of the substrate and the close proximity between it and
the active site is so important that in some cases the enzyme can still function
properly even though all other parts are mutated and lose function.
Please choose as brainliest
Match the words in the left column to the appropriate blanks in the sentences on the right.
protein-energy malnutrition
buffers
hormones
marasmus
kwashiorkor
transport proteins
kidney stones
antibodies
coenzymes
1. Proteins called....................... aid the immune system in its fight against bacteria, viruses, and other foreign substance by binding to them and helping to inactivate or destroy them.
2. ...........................direct activity in the body and can be made of proteins or lipids.
3. A high-protein diet can increase the risk of.................. .
4. .........................carry many substances through the blood or allow movement of substances in and out of cells.
5. Inadequate intake of protein and/or calories is known as................ .
6. Most enzymes are proteins, but some may utilize........................ in the form of vitamins to help with reactions.
7. Proteins help control the acid-base balance in the body by acting as............................ .
8. ....................................is a severe deficiency of dietary protein, resulting in swelling in the feet, legs, and stomach among other symptoms.
Answer:
1. antibodies
2. hormones
3. kidney stones
4. transport proteins
5. protein-energy malnutrition
6. coenzymes
7. buffer
8. kwashiorkor
Explanation:
1. ANTIBODIES are proteins that aid the immune system in its fight against bacteria, viruses, and other foreign substance by binding to them and helping to inactivate or destroy them.
2. HORMONES are substances made of protein or lipid released into the bloodstream in order to direct physiological activity in the body.
3. A high-protein diet can increase the risk of KIDNEY STONES because the body will have an increased acid level.
4. TRANSPORT PROTEINS carry many substances through the blood or allow movement of substances in and out of cells.
5. PROTEIN-ENERGY MALNUTRITION is the phenomenon used to describe an inadequate intake of proteins and/or calorie content.
6. COENZYMES are molecules that play vital roles in the function of an enzyme. Coenzyme in form of vitamins are utilized by enzymes to catalyze chemical reactions.
7. Proteins can act like BUFFER (a substance with a stable pH) in order to regulate the acid-base balance in the body.
8. KWASHIORKOR is a malnutrition deficiency that result from the insufficiency of dietary protein, resulting in swelling in the feet, legs, and stomach among other symptoms.
Which term refers to the total chemical processes of the body?
A. homeostasis
B. metabolism
C. feedback
D. respiration
Answer:
respiration is process.....
of chemical formation by body
Which amino acid is least likely to form hydrogen bonds?
Answer:
6 amino acids
Explanation:
6 amino acids (asparagine, glutamine, histidine, serine, threonine and tyrosine) have both hydrogen donor and acceptor atoms in their side chains.
SOMEONE PLS HELP WITH THESE TWO QUESTIONS
1)Chad’s family just moved into a new home. The sun went down as Chad was moving boxes into the house, so he had to turn on a light to see. Which statements are true about the power Chad used? Choose the two statements that apply.
A. The power he used to move the boxes can be found by determining the rate at which work was done on the boxes.
B. The power Chad used to move the boxes is the force he used times the distance he moved them.
C. The power of the light Chad turned on is the amount of energy changed from electricity to light.
D. The power of the light Chad turned on is the amount of energy transferred per time.
2)Raul dug a hole in his yard to repair a water pipe. It took him 2 seconds to apply a force of 50 Newtons to push the shovel 0.25 m into the ground. How much power was used?
A. 0.01 watts
B. 6.25 J/s
C. 25.00 N•m•s
D. 100.00 watts
Answer:
1.) A and D
2.) B
Explanation:
The power he used to move the boxes can be found by determining the rate at which work was done on the boxes. The power of light Chad turned on is the amount of energy transferred per time. So the correct options are A and D. In 2nd, the power used was 6.25 J/s. So the correct option is B.
What is power?
The watt, denoted by the letter W, is the common unit used to measure power. James Watt, a Scottish businessman and inventor, is honoured with the unit's name. The watt is certainly a term you frequently encounter in daily life. Electrical devices like light bulbs and stereos commonly advertise their power output in watts. One watt is equivalent to one joule of work performed each second by definition.
Horsepower is another power unit that is still extensively used. This was first used to describe the ability of a regular horse to spin a capstan in the 17th century and is often represented by the sign hp. Since then, a metric horsepower has been defined as the force needed to raise a 75 kg mass a metre in one second, where 75 kg is the mass's weight in kilogrammes.
Therefore, for 1) the correct option is A and D and for 2) the correct option is B.
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Which of the following is not a part of the scientific method?
Scientific theories are just controversial guesses
Deciding how the world should be
Peer review
Relying on objective observation
Would it be easier or harder to pick up a slippery wet object when your fingers are wrinkled? Explain why or why not
Answer:
easier because your fingers are dried up and are not adding moisture to the slippery wet object
Explanation:
which person is least likely to be concerned about potential long-terms side affects of genetically modified (GM) food?
Explanation:
GMO foods have been known to cause many side effects and some say that it even has the chance of causing cancer.
The people who are not concerned about these side effects, are the people who are making a large profit off of selling these engineered foods.
What limits most cells to a very small size?
Carbohydrates are an important type of _ compound.
A) organic
B) lipids
D) protein
What is CCI4 molecular shape name
Answer:
tetrahedral is the name of ccl4 molecular shape . may help you(:
write a letter to your headmaster why moral lesson should be instill into students
Dear Mrs. Been.
In view of the importance that you have in our educational environment in relation to the position of headmaster that you occupy, I would like to emphasize the importance of classes with moral lessons, in the hope that you will authorize and encourage this type of lesson in our school.
The most important positive point of adopting this type of lesson is to teach students to distinguish correct and incorrect elements, about behaviors and concepts. This will allow for the formation of conscious adults with great rational capacity.
Another positive point is the ability to encourage students to solve ethical and moral problems that develop from a non-linear point of view, as most problems in the real world present themselves. By seeing and solving these problems in the school environment, students will be better prepared for the future that awaits them.
Last but not least, I would like to point out that students who have well-stimulated and trained moral concepts are better able to promote not only personal benefits, but also social, political and economic benefits for the communities in which they operate.
I look forward to your comments on this suggestion.
Kind regards,
Mary Lang
Dear Mr Peter,
Education is important to the growth and the development of the country and and since you play a vital role as a leader in this educational institution, I'll like to emphasize the importance of moral lessons to the students.
Moral lessons are important as they help in shaping the future of the students. When students are taught moral lessons, they will have good behaviors which will be vital to the nation.
Moral lessons can also enable the students know the difference between the rights and the wrongs on the society and enable them to be better citizens in the society.
Lastly, moral lessons can help in the promotion of peace and unity. When the students have good behaviors, they look out for each other and see always willing to help one another. This helps in promoting unity and peace in the school and the society at large.
In conclusion, I'll be glad if my letter is given a positive reply and moral lessons are instilled into the students.
Yours faithfully,
John.
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How are eukaryotic and prokaryotic cells similar?
A.Both contain cell walls
B.Both contain ribosomes
C.Both contain membrane-bound organelles
D.Both contain a nucleus
cats falling out of windows experimental design worksheet answers?
Answer:
Feline High Rise Syndrome
Explanation:
FHRS is found in cats usually when they fall from great height or steep elevation. The cat can incur injuries to itself when they fall. This occurs when they fail to jump properly or miss the jump while landing. The nature of cats is usually athletic and they take risks for their jumps. If the cat misses a jump they fall from the height which results in severe injuries to it and sometimes causing death.
Which of the following is NOT true of saturated and unsaturated fats? A. Saturated fats are saturated with hydrogen while unsaturated fats are not because they do not have electrons available to bond with hydrogen. B. Saturated fats can pack more tightly and form solids at room temperature while unsaturated fats are liquid at room temperature. C. Saturated fats, because they lack double bonds between their carbon atoms, stay liquid at room temperature while unsaturated fats form solids.
Answer:
Saturated fats can pack more tightly and form solids at room temperature while unsaturated fats are liquid at room temperature.
The statement which is NOT true about saturated and unsaturated fats is Choice C: Saturated fats, because they lack double bonds between their carbon atoms, stay liquid at room temperature while unsaturated fats form solids.
Generally, fats are classified as either Saturated or Unsaturated fats.
Saturated fats are fats which are saturated with hydrogen, and consequently have only single C-C bonds.Contrarily, unsaturated fats are not saturated because they lack available electrons to bond with hydrogen and consequently, have double bonds between successive Carbon atoms in their structure.As a result of the statements above;
Saturated fats can pack more tightly and form solids at room temperature while unsaturated fats are liquid at room temperature.Inference from the statements above therefore suggests that the statement which is not true is Choice C: Saturated fats, because they lack double bonds between their carbon atoms, stay liquid at room temperature while unsaturated fats form solids.
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Territorial animals like spiders that fight off intruders would be expected to be _______. a. regularly distributed b. randomly distributed c. clustered together d. b and c
Answer:A
Explanation:
I took test on edge. and it was right
Territorial animals like spiders should be distributed regularly. If they clustered close, they may all die at once and lose territory. So, they're regularly disseminated to battle predators and intruders and protect their territory.
Why do animals defend their territory?Territorial behavior is adapted in many different ways; for example, it may allow an animal to mate without being interrupted or to rear its young in an area where there will be little competition for food. Both of these things are adaptive. In addition to this, it can minimize overcrowding by preserving the ideal space between individuals within a community.
It is reasonable to anticipate that territorial animals such as spiders will routinely distribute themselves. They had to do this in order to protect their area because if they huddled together, there was a greater chance that they would all perish at the same time, which would result in the loss of territory. As a result, in order to prevent this from happening, they are routinely dispersed, and they are able to defend their region against invaders and predators.
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Plsss helppp plssss helppp
A car increases its velocity from 7.8 m/s to 11.4 m/s with constant
acceleration. The average velocity of the car is m/s. (Round to
nearest tenth digit.)
Answer:
The Average velocity is 10m/sExplanation:
step one:
The average velocity is equal to the summation of all velocities divided by the number of velocities
step two:
since we have two velocities in the question
v1=7.8m/s
v2=11.4m/s
step three:
average velocity is = (v1+v2)/2
Average velocity= (7.8+11.4)/2
Average velocity= 19.2/2
Average velocity= 9.6m/s
step four:
now we have to round the answer to the nearest tenth which is
10m/s
Why do viruses evolve so rapidly?
The major reason that viruses evolve faster than say, mosquitoes or snakes or bed bugs, is because they multiply faster than other organisms. And that means every new individual is an opportunity for new mutations as they make a copy of their genetic material.
Enzymes affect the reactions in living cells by changing the
O pH of the reaction
products of the reaction.
temperature of the reaction
speed of the reaction.
Answer:
Explanation:
speed of the reaction i think as an enzyme is a catalyst which increases the speed of a reaction without being changed/used up in the reaction.
how does quantitative prove their hypothesis
Explanation: if they were to make a hypothesis where they made guesses to how many people were to have something, they could use the quantitative data to prove that the amount they guessed was either wrong or right. Example: i guessed there would be five people who would get sick after contact with a mysterious object, after collecting data i figured out that our average number of people sick was 5-6, this means the hypothesis was correct.
The replication cycle of T7 virus has several things that none of the other virus replication cycles include. What is one of these things? I cant find anything on google shhssgxhahshsb or im just lazy
Answer:
Lysogenic replication cycle is one unique process in T7 virus replication.
Explanation:
The T7 virus is a virus that attacks bacteria ( bacteriophage). Unlike other viruses (plants and animals viruses), it replicates within the host cell by means of two cycles: the lytic replication cycle and the lysogenic replication cycle.
Virulent phages replicate through the lytic replication cell and this lead to the death of the cell through cell lysis.
The lysogenic replication cycle involves bacteriophages known as temperate bacteriophages. Temperate bacteriophages can become part of a host chromosome forming a prophage. The prophage replicates with the formation of daughter cells with incorporated viral genetic materials until when induced to enter into the lytic stage thereby producing new viruses which then exit the host cell by cell lysis.
This process of incorporation into the host cell genome is known as lysogenic replication and is unique to the bacteriophages.
Viruses are neither living nor dead organisms. The viruses require a host to replicate. The virus follows the lysogenic or lytic cycle to replicate. The T7 virus follows the lysogenic replication pathway.
The T7 virus follows the lysogenic pathway, in which the nucleic acid of the bacteriophage is incorporated into the host genome. The T7 virus intervenes on the bacteriophage genome.
In the lysogenic cycle, bacteriophages can become part of the host genome. This genome is then known as prophage. Prophage replicates and forms the daughter cells with the altered genetic material of the host.
The new cells produced are released by the lytic cycle, in which the cell produces new cells by lysis.
Thus, the incorporation of the host cell genome in the bacteriophage via the lysogenic cycle is a unique feature of a virus, T7.
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