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2 years ago

Observations are things that can be perceived with senses (i.e., sight, sound, smell, taste, and touch).

Biology

2 answers:

AlexFokin [52]2 years ago

4 0

Sample Answer

What did you include in your response?

Joseph Priestly observed that a candle alone in a jar did not stay lit for long.
Priestly observed that adding a plant to the jar caused the candle to stay lit longer.
Priestly inferred that plants give off oxygen during photosynthesis, providing the oxygen needed for the candle to burn.
Priestly inferred that the burning candle gave off carbon dioxide, which was used by the plant.

mojhsa [17]2 years ago

4 0

Answer:

Joseph Priestley was a famous philosopher of the 18th century, who is famous for his experiments with the air, optics, electricity and soda water. His work was considered to be quantitative because he believes in practical application.

His experiment that leads to the famous discovery of placing a mice in a closed container with the mercuric oxide. He comes to know that mice survived because of common air-oxygen. He then finds the use of oxygen in the process of respiration and its use in the blood.

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Which of the following is most consistent with homeostasis? Select one: a. As blood pressure falls, blood flow to cardiac (heart

alex41 [277]

Answer:

Both C and E are reasonable answers.

Explanation:

Homeostasis describes the body's ability to maintain a stable equilibirum. In other words, if the body experiences a stress, it will generate a response that works to counteract that stress and restore itself to how it was prior to the stress.

A. This describes a cause and effect (BP down --> venous return down). It does not describe an active physiological response to counteract the BP drop such as an increase in heart rate. Not homeostasis.

B. Again, a cause and effect is described. Blood vessel walls becoming thinner is not a response to counteract increased BP. Not homeostasis.

C. Here a response to a stress is described. Men are drinking more water. The body responds by getting rid of that water, restoring the body to its former state. This describes homeostasis.

D. This sounds like homeostasis, but it's actually the opposite of what happens. Dilation of peripheral blood vessels is a way for the body to get rid of heat. This is the opposite of what you would want if the body got colder - it would make the stress worse, which is the opposite of homeostasis. In actuality the response to cold temperature is constriction of blood vessels to preserve heat.

E. This deescribes homeostasis. The stress is increased glucose. The body's response to manage it is to release insulin, which helps remove the glucose from circulation.

5 0

2 years ago

Primary spermatocytes are diploid (2n) cells with all of the organelles typically found in eukaryotic animal cells. Spermatogene

Aneli [31]

Answer: a. Genetic recombination (crossing over)

b. Can also be explained in terms of crossing over

c. Non disjunction of homologous chromosomes in meiosis 1

Explanation:

The process that allows for the transfer of both the paternal and maternal materials to is the crossing over process that takes at meiosis 1 changing them to secondary spermatocytes. While they are still primary spermatocytes, they are still diploid cells having both the maternal and paternal chromosomes. But since the spermatozoon is an haploid cell, it is able to retail some of both parents chromosome by the crossing over event which takes place between homologous paternal and maternal chromosomes allowing them to exchange materials. Thus the chromosomal contents of the primary spermatocyte differs from that of the spermatozoon.

C. This can occur as a result of the one of the homologous chromosome pair refusing to separate at meiosis 1 with one gamete containing 4 chromosomes/8 sister chromatids and the second having 2 chromosomes/4 sister chromatids.

3 0

2 years ago

The state of health and functioning of the liver is often assessed with dye-tracer techniques. The dye used most frequently is b

elena-s [515]

Answer

1.Radioactive or chemical decay

2. X(t) = Xoe^-kt

lnY(t) = -t + lnYo

4. 6.07mg

Explanation:

Let the liver and and blood compartment be represented by the symbol L and B respectively

For the liver

Suppose a first Order removal process started with an amount X, in which amount b disappeared in time t, the process is decay process which can be represented as follows,

∫dX/dt = -K1X

By rearrangement and integration;

∫dX/X = -K1t

ln X = -K1t + C

Since At t= 0, X = Xo then

C = lnXo

The equation becomes:

lnX = -K1t + lnXo

lnX - lnXo = -K1t

ln(X/Xo) = -K1t

X/Xo = e^-kt

X(t) = Xoe^-kt

X(t) = Xoe^-0.5t........(2)

Similarly for B (blood), suppose a first order flow flow of the dye move from the blood to the liver, let Y be the initial concentration, and amount b that has flown to the liver in time t

B---------> B(t)

t=0 Yo 0

t=t. Y-b. b

dY/dt = -K12(Y-b)...........(3)

Let Y-b = Y(t)

∫dY/dt = -∫K12t

By rearrangement and integration;

∫dy/Y(t) = ∫-K12dt

lnY(t) = -K12t + C1

at t= 0, C1 = ln(Yo)

Therefore ln Y(t) = -K12t + lnYo

But K12 =1

ln Y(t) = -t + lnYo.............(4)

(3) The assumptions used here

is that of a decay for the liver . The amount remaining taking as the amount of a substance

(4) using the equation 2,

X(t)= Xo e^-K1t........(2)

For time t = 1hour, and an initial amount X = 10mg, K = 0.5

X(t) = 10× e^-0.5

X(t) = 10 × 0.607

X(t) = 6.07mg

(5) within the scope of information presented, I have no data to make this judgment.

3 0

2 years ago

Which of the following phenomena is a consequence of Independent Assortment? 1. Pure breeding plants, when mated with each other

Natalka [10]

Answer: The answer is that the phenotypic ratio among phenotypes produced from an F1 X F1 dihybrid cross is 9:3:3:1.

Explanation:

Independent assortment of genes explains how alleles on different chromosomes arrange independently of one another during gamete formation.

So, a dihybrid cross involving TWO characters (e.g Seed color & seed shape) would have its respective alleles DISTRIBUTED whether dominant or recessive, for crossing to occur and yield varying proportion of offspring in the well spread ratio of 9:3:3:1; making it a consequence of independent assortment of genes

7 0

2 years ago

Which of the following statements is CORRECT regarding studies of character

pishuonlain [190]

Answer:

Explanation:

Assume that a student is given two different models of bacteria, with one model consisting of big bacteria and the other consisting of small bacteria. How can the student demonstrate the theory of endosymbiosis using the models?

5 0

2 years ago