Hello there! Photosynthesis
Objectives:
(Adaptable to grade levels 6-9)
The student will:
1. Observe evidence of photosynthesis in a water plant.
2. Assemble the equipment needed to measure the rate of photosynthesis in
elodea (water plant).
3. Count bubbles of oxygen gas given off by elodea to determine the rate of
photosynthesis.
4. Change the conditions of photosynthesis by altering light intensity and
carbon dioxide amount, and determine the effects on the photosynthesis rate.
5. Prepare a graph of the collected data and analyze it.
Materials Needed:
(For each group of four students)
elodea (water plant) lamp (40 watt)
test tube razor blade (single-edge)
dechlorinated water (room temperature) tape
sodium bicarbonate powder (baking soda) clock or timer
metal stand with rod or test tube rack metric ruler
Strategy:
PART A. Setting Up the Experiment
1. Obtain a sprig of elodea. Remove several leaves from around the cut end of
the stem. Slice off a portion of the stem at an angle and lightly crush the
cut end of the stem.
2. Place the plant into the test tube, stem end up, filled with water.
3. Secure the test tube to a metal stand with tape or place the test tube in a
test tube rack.
PART B. Running the Experiment
1. Place a 40 watt lamp 5 cm from the plant. After one minute, count and
record the number of oxygen bubbles rising from the cut end of the stem.
Count bubbles for five minutes. If bubbles fail to appear, cut off more of
the stem and recrush.
2. Run a second five-minute trial. Record and average your results.
3. Move the lamp so it is 20 cm from the plant. After one minute count and
record bubbles for two five-minutes trials. Again, average and record your
results.
4. Add a pinch of sodium bicarbonate powder to the test tube. Place the lamp
5 cm from the test tube. After one minute, record bubbles for two five-
minute trials. Average and record your results.
5. Prepare a graph of your results. Use the average number of bubbles for the
vertical axis. Use the type of environmental condition for the horizontal
axis.
Performance Assessment:
The students will answer these questions using specific values from the
investigation. Diagrams may be included.
1. How does this investigation demonstrate that plants give off oxygen during
photosynthesis? Explain your answer based on your observations.
2. How does the rate of photosynthesis change when the light source is moved
from a distance of 5 cm to 20 cm?
3. How does the rate of photosynthesis change when sodium bicarbonate is added
to the water?
Conclusions:
Plants use green pigments called chlorophylls to trap light energy. The
chlorophylls give a plant its green color. Inside the cells that have
chloroplasts, the light energy is used to make a simple sugar called glucose.
The process by which plants use light energy to make glucose is called
photosynthesis.
During this process of sugar production, carbon dioxide combines with water to
form glucose and oxygen is released. Oxygen that is produced in photosynthesis
is given off as a gas. If a lot of oxygen is being given off, photosynthesis is
occurring rapidly. If little oxygen is being given off, photosynthesis is
occurring slowly. The amount of trapped light energy and the amount of carbon
dioxide available affects the rate of photosynthesis.
The purpose of adding sodium bicarbonate powder to the water increases the
amount of carbon dioxide in the water.
This investigation can be performed with water plants grown in many parts of
the world, except regions that have permanent ice.
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The bubbles released by the Elodea signify that the plant is cycling matter because:
carbon is being fixedoxygen is being releasedCarbon in the form of carbon dioxide is being fixed in the Elodea through the process of photosynthesis according to the following equation:
[tex]6CO_2 + 6H_2O ---> C_6H_1_2O_6 + 6O_2[/tex]
During respiration by the same Elodea, the carbohydrate produced would be broken down in a reaction with oxygen to produce carbon dioxide and water:
[tex]C_6H_1_2O_6 + 6O_2 ---> 6CO_2 + 6H_2O[/tex]
Thus, important materials such as carbon and oxygen are being recycled in the photosynthetic process.
More on matter recycling can be found here: https://brainly.com/question/1192312
which element is NOT found in DNA? a. Nitrogen b. oxygen c. sulfur
Answer:
sulfer
Explanation:
Why is it important for farmers to add nitrogen to their field of crops?
O Plants use nitrogen to make nucleic acids which provide energy.
O Plants use nitrogen to make carbohydrates which provide energy.
o Plants use nitrogen to make proteins which help them grow strong and healthy.
Plants use nitrogen to make lipids which help them grow strong and healthy.
Answer:
itrogen is one of the key nutrients that plants need to grow, and it is naturally available in limited quantities. Therefore, the addition of nitrogen fertilizer is an important component of achieving high agricultural yields.
Explanation:
Which of the following is NOT a property of water?
O A) It is a good solvent.
OB) It is denser when frozen than when liquid.
OC) It resists temperature changes.
OD) it is cohesive.
O El It can be found as a solid. liquid. or gas.
Answer:
It is denser when frozen than when liquid.
Explanation:
Ice is actually less dense than water. The lattice arrangement of ice allows water molecules to be more spread out than in a liquid, making ice less dense than water.
Hope that helps.
in chemical reactions, bonds blank in reactants.
Which of the following is an example of natural selection?
A
Over time, the Earth's crust started to solidify about one-billion years after the
planet was formed.
B
Over time, a species of cricket became green because green crickets were better
able to hide among the leaves.
с
In the winter, as food becomes more scarce, some species of birds fly to new
habitats in the south.
D
In June, the Northern Hemisphere gets more direct sunlight due to the tilt of
Earth's axis as it revolves around the sun.
Answer:
its b
Explanation:
i just did it :)
Science is an attempt to explain
A. the truth concerning all things in Science
B. the supernatural
C. superstitions
D. natural phenomena
Answer:
its D i took the k12 test i hope this helps
Explanation:
please help soon!!
Erwin Chargaff's work on the composition of nucleic acids began in 1944. His findings, which later became known as
Chargaff's rules, detail the specific pairings that occur in double-stranded DNA molecules.
According to one of Chargaff's rules, a section of DNA molecule that contains 50 base pairs and has 15 adenine
bases must also contain
a- 15 guanine bases
b- 15 cytosine bases
c- 15 thymine bases
d- 15 uracil bases
Answer:I think 15 cytosine based
Practice Classify each of the following examples as toxic, sediment, nutrient, and/or bacterial pollution.
Explain your classifications.
A Logging removes trees from a hill, leaving a barren landscape.
Classification:
Explanation:
Answer:
Sediment pollution
Explanation:
There is no more vegetation on the hill to prevent sediment from being carried away
Logging removes trees from a hill, leaving a barren landscape is sediment pollution.
Pollution refers to any contamination of the natural environment with unwanted material or energy which renders the environment unfit for life. There are many kinds of pollution that affect various spheres of the environment such as land, air water etc.
When trees are logged from a hill in such a manner that the landscape is left barren, sediments can now easily be washed away by runoff into surrounding water bodies or other areas. This is an example of sediment pollution.
Learn more: https://brainly.com/question/24577840
Which of the following describes all animals? A. All animals have backbones. B. All animals are multicellular. C. All animals control their own body temperature. D. All animals are vertebrates.
Answer:
b
Explanation:
Answer:
B, definitely B.
Explanation:
Answer the question above
Answer:
i think it's March
Explanation:
The movement of organisms from one place to another is called ___________. *
Answer:
Dispersal
Explanation:
football measurnet and draw it
Answer:
eefedsgechtghjffrturgdhudcn7ddrzvj
in which amino acid imidazole group found
Answer:
Histidine contains imidazole group which can be uncharged or positively charged, depending on its local environment. Lysine & arginine contains positively charged R group while glutamate has negatively charged R group.
Which of the following correctly summarizes the development of the fetus during the second trimester?
Body functions, reflex development, and skin details
Cell division and tissue specialization
Gastrulation, neurulation, and rhythmic breathing
Specialization, function, and growth
Answer:
Body functions, reflex development, and skin details
Explanation:
The second trimester marks the period between the thirteenth to the twenty-sixth week. During this period of fetal development, the fetus begins reflex development such as sucking and swallowing. He is also now able to respond to stimuli.
Body functions are also developing at this stage. The baby can now kick, turn, and move his body. The brains are developing, the hairs and fingernails are also beginning to develop.
Skin details are also developed at this stage. For example, the vernix caseosa is produced to protect the skin of the fetus.
Select all that apply: What are some of the steps of the
scientific method mentioned?
Answer:
Make an observation.
Ask a question.
Form a hypothesis, or testable explanation.
Make a prediction based on the hypothesis.
Test the prediction.
Iterate: use the results to make new hypotheses or predictions.
Explanation:
What is the role of energy in living organisms? Is ti a mor or less important role than other characteristics of life?
Answer:
A huge number of chemical reactions take place continuously in a living cell. The whole of all chemical processes, that is, the total turnover of matter and energy is called metabolism.
Explanation:
All organisms need the energy to grow, reproduce, and respond to their surroundings. All these processes are achieved through metabolism that allows the energy available to them.
I need help with this please
Answer:
the amount of carbon in the cycle can increase or decrease based on the number of factories present.
Explanation:
In the carbon cycle, carbon is exchange along many different forms on earth. Carbon is the main component of biological compounds, and it is released from organisms when they die or when fossil fuels are burned, hence, the diagram demonstrates this.
ASAP ASAP 50 POINTS
In three to four sentences explain both the positive and negative effects of mutations.
Answer:
positive mutations means positive impacts of mutations i.e it leads to mutations. while negative effects leads to chromatic aberration that occurs during phenyl ketonuria!
If this helped you mark me brainliest (=^o^=)
If f(x) = 3x - 1 and g(x) = x + 2, find (f- g)(x).
Rrgggggg
Answer:
(f - g)(x) = 2x - 3
General Formulas and Concepts:
Pre-Algebra
Distributive PropertyAlgebra I
Combining Like TermsExplanation:
Step 1: Define
f(x) = 3x - 1
g(x) = x + 2
(f - g)(x) is f(x) - g(x)
Step 2: Evaluate
Substitute: (f - g)(x) = 3x - 1 - (x + 2)Distribute -1: (f - g)(x) = 3x - 1 - x - 2Combine like terms: (f - g)(x) = 2x - 3please give an perfect answer
Answer:
a neutral solution? i think
Help me please !!!
Which event in meiosis increases genetic variation within a population?
A. DNA condenses to form chromosomes.
B. Segments of chromosomes cross over.
C. Chromosomes duplicate themselves.
D. Chromosomes form pairs.
Answer:
Because of recombination and independent assortment in meiosis, each gamete contains a different set of DNA. This produces a unique combination of genes in the resulting zygote. Recombination or crossing over occur during prophase 1
HI EVERYONE ^_^
Why the ureolytic bacteria produce CaCO3?
Answer:
Ureolytic bacteria hydrolyze urea to generate ATP by the efflux of ammonium ions through ATP-synthase, producing carbonate. In the presence of calcium ions in excess, calcium carbonate will precipitate.
Will give 100 points!! ASAP
Animal life in the Paleozoic Era included all of the following EXCEPT ____. a. marine life c. amphibians b. humans d. reptiles
what are the steps in the digestion of protein
Explanation:
Protein digestion begins when you first start chewing. There are two enzymes in your saliva called amylase and lipase. They mostly break down carbohydrates and fats. Once a protein source reaches your stomach, hydrochloric acid and enzymes called proteases break it down into smaller chains of amino acids.
hope it helps!
Carnations with red, smooth petals are crossed with carnations with white, rough petals. In the F1, all the petals are pink and smooth. The F1 intercross yields the following F2:3/16 red, smooth6/16 pink, smooth3/16 white, smooth2/16 pink, rough
1/16 red, rough1/16 white, rougha) What are the parental genotypes?b) What are the F2 genotypes and phenotypes?c) What conclusions can be made about the allelic and gene interactions for both the petal color and texture alleles?
Answer:
a) What are the parental genotypes? RRSS and rrss
b) What are the F2 genotypes and phenotypes?
F2) 3/16 RRSS + RRSs (red, smooth)
6/16 RrSS + RrSs (pink, smooth)
3/16 rrSS + rrSs (white, smooth)
2/16 Rrss (pink, rough)
1/16 RRss (red, rough)
1/16 rrss (white, rough)
c) What conclusions can be made about the allelic and gene interactions for both the petal color and texture alleles? For petal color, it occurs incomplete dominance, being R the dominant allele for red and r the recessive allele for white, together expressing pink in heterozygosis. For texture, it occurs complete dominance of the allele codifying for smooth, S, over the allele codifying for rough, s.
Explanation:
Due to technical problems, you will find the complete answer and explanation in the attached files.
Do hawks eat spiders?
Answer:
yea
Explanation:
if they can catch it
A small loop of DNA that can get transferred from one bacterium to another bacterium is called a: A. Nucleus B. Plasmid C. mRNA D. Genophore
If any of y’all can give me the definition for these words I will give 5 stars ,like and brainlest or whatever it’s called
Answer:
rRNA - Ribosomal RNA, a molecular component of a ribosome, the cell's essential protein factory. Strictly speaking, ribosomal RNA (rRNA) does not make proteins. It makes polypeptides (assemblies of amino acids) that go to make up proteins
tRNA - Transfer ribonucleic acid (tRNA) is a type of RNA molecule that helps decode a messenger RNA (mRNA) sequence into a protein. tRNAs function at specific sites in the ribosome during translation, which is a process that synthesizes a protein from an mRNA molecule.
Explanation:
In a plant, leaf color and leaf shape are controlled by two linked genes. Leaves of the wild plant are red (R) while a recessive mutation in this gene causes leaves to be white (r). Wild-type leaves are pointed (P), while a recessive mutation in this gene causes them to be smooth (p). For a parent plant that is heterozygous for both traits with both recessive mutations on one chromosome, what genotypes will its gametes be
Answer:
The genotypes of the gametes are:
RP (parental), rp (parental), Rp (recombinant), rP (recombinant)
Explanation:
Available data:
Leaf color and leaf shape are controlled by two linked genes.Leaves of the wild plant are red (R) while a recessive mutation in this gene causes leaves to be white (r).Wild-type leaves are pointed (P), while a recessive mutation in this gene causes them to be smooth (p). Parent plant heterozygous for both traits with both recessive mutations on one chromosomeParent) RP/rp ---> RP are in one chromosome, while rp in another
chromosome
Gametes) RP (parental)
rp (parental)
Rp (recombinant)
rP (recombinant)
HELPP ASAPP PLEASE !!!!
Answer:
galaxy x and z