Answer:
- Typically begins about 20 minutes after stage 1: Stage 3
- Alpha waves dominate: Stage 1
- Sleep spindles occur: Stage 2
- Light sleep: Stage 2
- Vital signs are at their lowest levels: Stage 4
- Delta waves dominate: Stage 4
- Feeling a drifting sensation: Stage 1
- Beginning of decline in respiration and blood pressure: Stage 2
Explanation:
Sleep can be divided into two phases: 1-non-rapid eye movement (NREM) sleep and 2-rapid eye movement (REM) sleep. In turn, NREM sleep is divided into four stages (1 to 4). Stages 1-2 are referred to as “light sleep”, while stages 3-4 are known as “deep sleep”. The first NREM stage (normal length: 5-10 minutes) is the transition between wakefulness and sleep. During this stage, the brain produces high amplitude theta waves. During the second NREM stage (light sleep, 10-25 minutes), the body temperature drops, muscles are in a more relaxed state, the breathing and heart rate also drop. The third NREM stage (20-40 minutes) involves the emergence of delta waves and muscles are entirely relaxed. This period (stage 3) is a period of deep sleep, which is referred to as slow-wave sleep (SWS). Finally, the fourth NREM stage (10-60 minutes) is characterized by high amplitude delta waves, while heart and respiration rates slow dramatically.
A key difference between primary cell cultures and secondary cell lines is that:____.a. primary cell cultures tend to stay alive and divide longer than secondary cell lines. b. secondary cell lines are generally cancerously transformed and will divide indefintely. c. secondary cell lines grow slower than primary cell cultures.d. the cells in primary cell cultures do not divide.
Answer:
d. the cells in primary cell cultures do not divide.
A key difference between primary cell cultures and secondary cell lines is that the cells in primary cell cultures do not divide.
hope it helped you
Explanation:
The main difference between primary and secondary cell culture is that the primary cell culture contains the cells directly obtained from host tissue, whereas the secondary cell culture contains sub-cultured cells from primary cell culture.
Why are temperatures hotter in locations near the equator?
Is there a particular type of fiber that is found mostly in the mucous connective tissue???
Explanation:
connective tissue. The fixed and transient cells found in connective tissue. ... Collagen fibers - most are type I collagen (most abundant protein in the body) ... It provides tensile strength in multiple directions. slide.
what is the main purpose of the pupil
Answer:
to adjust how much light is let into the eye
Explanation:
Answer:
The pupil is where light enters the eye. How much light is controlled by the iris which surrounds the pupil and opens and closes it like a camera lens aperture.
Q.#23.Lymph nodes are soft, small, round- or bean-shaped structures. They usually cannot be seen
or easily felt. They are located in clusters in various parts of the body, such as the: Neck, Armpit, Groin
and Inside the center of the chest and abdomen. At times these areas used to be swollen up for few days and are
gone. Explain why these swollen experiences are important.
Answer:
Lymph nodes swell to protect us from illness if they do not swell non fatal illnesses could spell out death
Explanation:
2. What does it mean for a species to have high biological fitness? Explain in terms of survival and reproduction
Answer:
FITNESS IS THE ABILITY TO REPRODUCE FOR ANY ORGANISM
IF THEY CAN'T REPRODUCE THEY WON'T EXIST
Explanation:
This mountain slope towers over a town several hundred feet below. Which two weather events present the highest risk to the town
what are the three functions if cnidarians gastrovascular cavity?
Answer:
Digestion, distribution of nutrients throughout the body, and it can serve as a hydrostatic skeleton.
which among the following is not a part of pistil option a ovary option B stigama option c vein option d style
Answer:
c vein option
Explanation:
veins are parts of animals, not plants
plz explain in your own words
what are conjugated molecules????
Which of the following is a skin sensory receptor for touch?
A) Pacinian corpuscle
B) Meissner's corpuscle
C) Ruffini body
D) free nerve ending
Meissner's corpuscle is a skin sensory receptor for touch.
Meissner corpuscles are responsible for the sense of touch or light pressure, that is, they are very sensitive to the movement of objects on the skin and to very low vibrations.
About Meissner corpuscles:
• They are located on the lips and fingertips and are very sensitive.
• Meissner corpuscles act when there is a soft and light touch, and when vibrations are less than 50 hertz.
• These receptors can be altered when there is the presence of diseases where both thermal and tactile sensitivity are altered.
Therefore, we can conclude that Meissner corpuscles detect fine touch, that is, they are receptors on the skin that are sensitive to low-frequency vibration.
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What processes found at a divergent boundary will help form the following rocks?
Answer:
B
Explanation:
What is a divergent boundary:
In plate tectonics, a divergent boundary is a linear feature that exists between 2 tectonic plates moving away from each other.
They can produce rifts, which become rift valleys.
Divergent boundaries also form volcanic islands, which occur when the plates move apart to produce gaps that magma rises to fill.
Sedimentary rocks form due to deposition, and accumulation
Metamorphic rocks form in a transformation of existing rock to new rock in a process called metamorphism.
Igneous rocks form through the cooling and solidification of magma or lava.
When the filled gaps of magma cool off, it will produce igneous rocks.
Count the number of breaths you take in a minute and compare it with the number of times a fish opens and closes its mouth
Answer:
Don't know sorryyyyyyyyyyyyyyyyyyyyyyyyyyyyy
This organelle is considered the location for genetic material.
Answer:
The nucleus contains most of the genetic material (DNA) of the cell. ... Also located in the nucleus is the nucleolus or nucleoli, organelles in which ribosomes are assembled.
How does excretion takes place in amoeba
Answer:
excretion takes place through body surface by simple diffusion
Answer:
Amoeba is a unicellular organism living in fresh water bodies. The waste materials are excreted by the process of diffusion through general body surface. Contractile vacuoles also play some role in removal of waste materials.
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have a nice day
on
Directions: Choose the correct answer listed from the box below and then
write the letter of your answers a separate sheet of paper for your
answers.
1. It is formed from the fossilized remains of prehistoric plants and
animals
2. An earth's material results from the rock fragments that have been
created physical weathering.
3. Another earth's material naturally occurred in solid substances that
are composed of ions and molecules bonded together.
4. The materials are derived from nature and used by the people to
survive or satisfy needs.
5. The place where natural resources are rich has fertile arable lands
and home to the largest metallic minerals
6. To use without being completely used up or destroyed
7. A practice to use the resources wisely
8. A renewable resource produces the most electricity
9. An energy resource that will run out in the next several years
10. Renewable energy coming from the sun
4.Non-renewable
E. Philippines
II. Sustainable
B Hydroelectric
F. Minerals
J. Fossil fuel
C. Soil
G. Natural resources
K. Solar Energy
D. Conservation
How are cells able to guarantee that are DNA is always replicated correctly every time? 
Help will give brainl
what happens to water when it boils
Answer:
When water starts boiling evaporation takes place
Receptors trigger one of two effector pathways resulting in changes in neuronal activity. These changes will, ultimately, effect gene expression. Which effector pathway is characterized by ion flux through transmitter-activated channels resulting in an altered membrane potential and neuronal activity
Complete question:
Receptors trigger one of two effector pathways resulting in changes in neuronal activity. These changes will, ultimately, effect gene expression. Which effector pathway is characterized by ion flux through transmitter-activated channels resulting in an altered membrane potential and neuronal activity?
A. Slow effector pathways
B. Modulated effector pathways
C. Rapid effector pathways
D. NMDA glutamate receptor pathways
Answer:
D. NMDA glutamate receptor pathways
Explanation:
The NMDA glutamatergic receptor is a cationic channel receptor modulated by a ligand that allows the transport of Na+, K+, and Ca2+. Under certain situations, it exhibits particular permeability to Ca2+. The receptor has different regions that are susceptible to modulation by endogenous and exogenous agents. The receptor can be found at most excitatory synapses, where it responds to the neurotransmitter glutamate. During synapsis, the presynaptic membrane releases L-glutamate, which is received by NMDA glutamatergic receptor. The receptor plays a regulatory role because activates signaling cascades that depend on calcium.
These receptors are involved in normal synaptic transmission, in a diverse physiological phenomenon, and might be responsible for neurodegenerative processes.
The NMDA glutamergic receptor is characterized by ion flux through transmitter-activated channels resulting in membrane potential.
What are transmitter-activated channels?Transmitter-activated channels are channels through cell membranes which are activated by binding of transmitters.
An example of a transmitter-activated channels is the NMDA glutamergic receptor.
The NMDA glutamergic receptor is a ligand-gated cationic channel that allows calcium, potassium and sodium ions through it.
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Coffee trees grown in the shade of taller forest trees produce fewer coffee beans than trees grown on cleared forestland. However, unlike coffee grown in full sun, shade-grown coffee preserves some habitat for forest birds and other organisms. What is one advantage of growing coffee in the shade?
A. It harms the environment.
B. It provides farmers with greater profits.
C. It costs more than other growing methods.
D. It helps maintain forest biodiversity.
Answer:
d
Explanation:
provides animals with homes letting them breed
It helps maintain forest biodiversity. Therefore, option (D) is correct.
One advantage of growing coffee in the shade is that it helps maintain forest biodiversity. By growing coffee trees in the shade of taller forest trees, farmers preserve some habitat for forest birds and other organisms, which can help to maintain the overall biodiversity of the forest ecosystem.
This is particularly important in regions where forests are being cleared for agricultural purposes, as it can help to mitigate the negative impact on the environment.
While shade-grown coffee may produce fewer coffee beans than trees grown on cleared forestland or in full sun, it provides important ecological benefits that are not captured by purely economic considerations
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B 3.1 Suggest which leaf carries out more photosynthesis and explain why. Below is a section of part of a plant as seen with a light microscope. (4) E e 3.2 Provide labels for: (a) different types of cells A, B and C (3) (b) structure D (c) The waxy, water-repellent layer E Provide a suitable heading for the above diagram (1) (1) 3.3 (1)
The leaf that carries out more photosynthesis is the bigger leaf since it has a larger surface area and will have more chloroplasts.
The labeled parts of the plants are found in the attachment.
A suitable heading is "parts of a plant".
What is the role of chloroplasts in photosynthesis?Chloroplasts play a crucial role in the process of photosynthesis, which is the primary means by which plants, algae, and some bacteria convert light energy into chemical energy.
Chloroplasts are the organelles where photosynthesis occurs, and they provide the necessary structures and molecules for capturing light energy, generating ATP and NADPH, and converting carbon dioxide into organic compounds.
They are essential for the survival and growth of autotrophic organisms and form the basis of the food chain on Earth.
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Select the correct answer.
How does the high specific heat of water help maintain the temperature of earth?
A By heating and cooling more slowly than land or air
B. By heating and cooling faster than land or air
с.
By heating faster but cooling more slowly than land or air
The high specific heat of water help maintain the temperature of the Earth by heating and cooling more slowly than land or air. Thus, the correct option is A.
What is the specific heat of water?The specific heat of an object is the amount of heat which is required to increase or raise the temperature of unit mass of that particular substance through one degree celsius. Specific heat is represented by the symbol 'c'. Its unit in SI system is Joule /(kg °C) and in CGS is cal / (gm °C).
The high specific heat of water helps in regulating the rate at which air changes its temperature, which is why the temperature of the planet change between different seasons is gradual rather than sudden, especially the geographical locations near the ocean.
Therefore, the correct option is A.
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Match each of the following muscles with its correct description.
a. sternohyoid
b. hyoglossus
c. frontalis
d. mentalis
1. originates on the sternum and clavicle
2. classified as an infrahyoid muscle
3. consists of two bellies
4. elevates and protrudes lower lip
What two different components of a telescope can be used to focus light?
Answer:
Mirror and Lens
Explanation:
Refracting telescopes use lenses to focus the light, and reflecting telescopes use mirrors
write paragraph about digestion of food in brief
Answer:
Digestion is the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma. In certain organisms, these smaller substances are absorbed through the small intestine into the blood stream.
Explanation:
according to wikipedia!
Digestion is nothing but breaking down of substances into simpler forms, which the body can use. We eat many things and they have very complex compounds, our body cannot use these compounds. So, different parts of our digestive system breaks down different compounds to simpler forms, so that our body can use it for different functions.
What is the meaning of reality???
Answer:
life is nothing
Explanation:
i want to die
Answer:
reality means real real things or the real nature of things rather than imagined, invented,
3. Identify the natural cycle that is shown in the diagram. Then, for each box in the diagram, write one or two sentences explaining the labeled process as it relates to this cycle.
Answer:
the oxygen/carbondioxide cycle
Explanation:
decay creates carbon-dioxide, and plants does both cellular respiration and photosynthesis since plants are still alive. and there is oxygen and carbon-dioxide in rocks. basically the living mostly use cellular respiration and photosynthesis and non-living (the ocean and factory) produce oxygen and carbon-dioxide
What is the form of lipids, protein and carbohydrate that can be absorbed through small intestine?
The oxidase test is another biochemical test used to distinguish aerobic versus anaerobic metabolism in microbes. Research the oxidase test and describe how it is performed. Include examples of oxidase-positive and oxidase-negative microbes in your answer.
Oxidase test is a biochemical test that is used to identify organisms that produce the enzyme oxidase.
Oxidase test is used to distinguish aerobic from anaerobic metabolism in microbes.
Aerobic metabolism is the use of oxygen to generate energy from a food source while anaerobic metabolism is the generation of energy with the absence of oxygen.
The procedure of oxidase test includes:
Place a piece of filter paper in a clean petri dish and add 2 or 3 drops of freshly prepared oxidase reagent.Using a piece of stick or glass rod (not anoxidized wire loop), remove a colony of the test organism and smear it on the filter paper.Look for the development of a blue-purplecolour within a few seconds as shown in colourBlue purple colour signifies oxidase positive organisms which includes Pseudomonas aeruginosa
Colourless signifies oxidase negative organisms which includes Escherichia coli
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Birds differ from their closest relatives, the reptiles, in what ways?
(choose all that apply)
the bones of reptiles are too lightweight to permit flight
birds are capable of powered flight, while some reptiles can glide
birds have feathers, reptiles have scales
only the birds lay eggs on land; the reptiles can only lay their eggs in water
the reptiles have a series of internal air sacs that allow a very efficient extraction of oxygen
birds are endothermic, while reptiles are generally ectothermic
1 pts
Answer:
birds have feathers, reptiles have scales
birds are endothermic, while reptiles are generally ectothermic
Explanation:
The main difference between birds and reptiles is that birds have feathers on their body while on the other hand, reptiles ahve dry skin and have scales. Reptiles are ectotherms, while birds are endotherms. An ectotherm relies on its external environment to regulate the temperature of its body whereas Endotherms are able to regulate their body temperatures by producing heat within the body.