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Exercise No. 9Investigating Pulse Rate

INTRODUCTION

The heart pumps blood trough blood vessels to all parts of the body. With each contraction of the heart, blood is forced into the arteries. This surge of pressure is felt in the arteries of the pulse. The rhythmic pulse can be felt anyplace where an artery is close to the surface of the body and can be pressed against some firm tissue.

The pulse rate is exactly equal to the heartbeat. Medical personnel use the pulse rate as one indication on how the heart is functioning. Heart rate is influenced by many things, such as age, sex, physiological state, psychological state and temperature. In this activity, you will investigate how several of these factors influence the pulse rate.

OBJECTIVES

1. Feel a pulse rate and determine pulse rates.2. Determine the effect of pulse rate of standing at attention, holding your breath, and breathing

into a bag, deep breathing and exercise.3. Make a line graph to show the effect of exercise on pulse rate.

MATERIALS

Clock or watch with second handPaper bags

PROCEDURE

Work in pairs. Throughout this activity you and your partner will take turn being the subject and the experimenter. First you must learn how to take the pulse.

1. Locate the pulse in your partner’s wrist.2. After you have sat quietly for 1 minute, have your partner count your pulse for 15 seconds.

a. Record this number in Table 1. Determine your pulse rate for 1 minute by multiplying the number by 4. Then record your pulse rate per minute in Table 1.

3. Repeat step 2 two more times. Then switch role with your partner.b. Record the results in table 1 and then determine your average resting pulse rate per

minute. Record your average resting pulse rate per minute. Record your average resting pulse rate according to your sex in Table 2.

4. The subject should stand stiffly at attention for 2 minutes. Then, while the subject is still standing at attention, the pulse should be taken by the experimenter for 15 seconds. Switch roles.c. Determine your pulse rate per minute by multiplying this number by 4. Record your

attention pulse rate in Table 2.

5. While seated, the subject should take a deep breath, exhale part of it, and hold the breath as long as possible. While breath id being held, the subject’s pulse should be taken by the experimenter for 15 seconds. Then switch roles.d. Determine your pulse rate per minute by multiplying this number by 4. Record your

breath-holding pulse rate in Table 2.

6. While seated, the subject should hold an open paper bag tightly over the mouth. Do not breathe through the nose. The subject should breath through the mouth from the air in the

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bag for 2 minutes. Toward the end of the minute, the pulse of the subject should be taken by the experimenter for 15 seconds. Then switch roles.e. Determine your pulse rate per minute by multiplying this number by 4. Record your

breathing-into-bag pulse rate in Table 2.

7. While seated the subject should take deep breaths regularly for 30 seconds. After the first 15 seconds, the pulse of the subject should be taken by the experimenter for the remaining 15 seconds of deep breathing.

Note: If you become lightheaded while taking deep breath, hold your breath for a few seconds.

f. Determine your pulse rate per minute by multiplying this number by 4. Record your deep-breathing pulse rate in Table 2.

8. The subject should step up and down from a study chair, run in place or do jumping jacks for one minute. Immediately after exercise, the subject should sit and the pulse should be taken for 15 seconds. Then it should be taken again after 45 seconds, so that a 15-second pulse is taken every minute for 6 minutes. Switch roles.

g. Determine each pulse rate per minute by multiplying this number by 4. Record your after-exercise pulse rates in Table 2.

h. Determine the class pulse rate averages for males and females in each activity and record them in Table 2.

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Exercise No. 9Investigating Pulse Rate

Name_____________________________________ Biology Schedule _____________ Instructor_________________________________ Group No. ___________________

Score _______________________

RESULTS AND OBSERVATIONS

Table 1. Pulse Rate

Trial Pulse Rate / 15 sec. Pulse rate / Minute

1

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Table 2. Effect of Activity on Pulse Rate

Activity Your Pulse Average Female Average Male Pulse Rate/min. Pulse Rate/min. Rate/min.

Resting Standing at attention Holding breath Breathing into paper bag Breathing deeply Exercise (I min. after) Exercise (2 min. after) Exercise (3 min. after) Exercise (4 min. after) Exercise (5 min. after) Exercise (6 min. after)

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DISCUSSION

1. How does your resting pulse rate compare with the average for your sex? What is illustrated by any difference between your resting pulse rate and the average?

__________________________________________________________________________

__________________________________________________________________________

2. Why do you take a resting pulse rate?

__________________________________________________________________________

__________________________________________________________________________

3. Why do you think that holding your breath or breathing into a bag affects the pulse rate?__________________________________________________________________________

__________________________________________________________________________

__________________________________________________________________________

4. Which activity increases your pulse rate the most? What does this increase indicate?

__________________________________________________________________________

________________________________________________________________________

5. What do you think is the relationship between physical condition and pulse rate after

exercise? Between physical condition and recovery time?

__________________________________________________________________________

_________________________________________________________________________

6. Construct a line graph to show what happens to your pulse rate after exercise. Put pulse rate per minute on the vertical axis and time in minutes on the horizontal axis.

7. Why do athletes often have a lower pulse rate than non-athletes?

__________________________________________________________________________

__________________________________________________________________________

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Exercise No. 10Urinalysis

INTRODUCTION

Animals must get rid of their body waste products of metabolism. In humans, the kidneys remove waste chemicals from the bloodstream and produce urine. Urine normally contains water, salts, and organic wastes. The amounts of each of these chemicals depend on the person’s health, diet and activity.

For urine test, doctors can learn much about the general health of an individual. Kidney malfunction urinary tract infections, liver diseases, and diabetes are just some of the problems that can be diagnosed using urinalysis. Urinalysis involves physical, chemical and visual examination. Color, volume, pH, protein content, sugar content, presence of blood cells and sediments are some of the characteristics, which are tested in medical laboratories.

OBJECTIVES

In this activity, you should be able to:1. Evaluate urine samples for transparency, color and odor.2. Test urine for the presence of sugar and protein.3. Measure the pH of urine sample.

MATERIALS

Artificial urine sample test tube holder Bunsen BurnerTest tube rack matches or striker 5% acetic acidGlucose test tape pH paper test tube

PROCEDURE

Part I. Physical Evaluation of Urine

One factor to observe in urine is its general appearance. Normal urine is transparent. Old samples of urine may be cloudy due to the presence of bacteria growing in the urine after the sample was collected. Fresh urine samples that are cloudy may be due to urinary tract infections or may indicate the presence of blood cells, pus or fat.

1. Obtain the test tube sample marked control and set it in the test tube rack. Examine the control sample of artificial urine.a. Evaluate the transparency of the sample. Is the urine sample clear or cloudy?

Record your observation in your data table.

The color of your urine depends in part on its concentration. Pale, dilute urine may be the result of drinking large volumes of fluids, but it may also indicate diabetes. Dark, concentrated urine may be the result of dehydration or fever. A smoky-red to reddish brown color indicates the presence of red blood cells in the urine. Vegetables and fruits as well as vitamins and other drugs can alter the color of the urine.

2. Evaluate the color of the sample.b. Record your observation in your data table.

The normal color of the urine may be altered by several factors. A foul odor in fresh urine can indicate of bacteria. Bacteria may be present as a result of urinary tract infection. A fruity

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odor indicates the presence of ketones in the urine. Ketones are products of the breakdown of fats, which can occur due to diabetes or starvation.

3. Evaluate the odor of the sample.c. Record your observation in your data table.

Part II. Chemical Evaluation of Urine

The sugar content of urine can be evaluated. Sugar can be present in the urine after eating a meal rich in carbohydrates or during the periods of stress. However, a consistent finding of sugar in the urine may indicate diabetes.

1. Test the control sample for sugar content. Dip the end of one 4-cm strip of glucose test tape into the sample. Follow the direction on the test-tape package and compare your test tape to the color chart on the test tape dispenser.a. Record the sugar concentration of the sample in your data table.

Usually, urine is slightly acidic, having a pH near 6.0. The normal range may vary from 4.7 – 8.0. Several factors including food, dieting, stress, drugs, breathing rate and liquid intake, can affect the pH of the urine.

2. Test the control sample for its pH level. Dip the end of a one 4-cm strip pH paper into the sample. Compare the color of the test strip to the color chart on the pH paper dispenser.

b. Record the pH of the sample in your data table.

Protein in the urine indicates an abnormal condition called proteinuria. Proteinuria may result from disease or from damage of the glomeruli, Bowman’s capsules or nephron tubules, and is considered very serious.

3. Light your Bunsen burner. Hold the test tube containing the sample with the test tube holder. Carefully heat the top portion of the liquid by passing it through the Bunsen burner. Caution: Do not point the mouth of the test tube at anyone. After a short while, the liquid on the top portion will begin to boil. Watch for cloudiness to appear in this part of the liquid. Remove the test tube from the flame once the cloudiness appears or after a few seconds of boiling. If there is no cloudiness, no protein is present in the urine. If cloudiness does appear after boiling, add three drops of 5% acetic acid to the warm test tube. If the cloudiness disappears, there is no protein present. If the cloudiness remains, protein is present in the urine.

c. Record the presence or absence of protein in your data table.

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Exercise No. 10Urinalysis

Name___________________________________ Biology Schedule ________________ Instructor_______________________________ Group No. ______________________

Score __________________________

RESULTS AND OBSERVATIONS

Characteristic Sample 1 Sample 2 Sample 3

Transparency

Color

Odor

Sugar Content

pH Level

Protein

DISCUSSION

1. Why should a urine sample be fresh when it is tested?__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

2. What are the two physical changes that occur in urine after it had been acted on by bacteria ?__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

3. What are the three observations or tests that would indicate that a person has diabetes?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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4. What are the two ways that you might recognize blood in urine?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

5. What conclusions can you make about urine samples 1 and 2?________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

6. Why might a urine sample taken early in the morning differ from a sample taken soon after dinner?__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

7. When a baby wakes in the morning, his or her diaper may have an odor of ammonia. What causes this odor and why is this odor usually observed only in the morning?__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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Exercise No. 11Cellular Reproduction

INTRODUCTION

The process of cell division is fundamentally the same in all organisms. Attention is centered on the nucleus where the contained information, in the form of chromosomes, is equally divided between the products of division. Important changes also occur in the cytoplasm, but the morphological patterns associated with nuclear division are easier to follow. The division of the nucleus is mitosis. Mitosis may occur without cytoplasmic division or cytokinesis.

Although mitosis is essentially the same in both plants and animals, it varies in certain aspects due to structural differences in the cells of the two groups. To facilitate learning, mitosis has been divided into several stages or phases although the process is a continuous one. These phases are: prophase, metaphase, anaphase and telophase.

Many important events of mitosis occur before morphological changes are evident in each phase. For example, the chromosomes replicate and energy stores are accumulated. The morphological events of mitosis can be considered a mechanism for the orderly distribution of chromosomes to daughter nuclei.

OBJECTIVE

To illustrate and identify the different stages of cell division in order to determine the significant consequences of mitosis.

Stages of Mitosis

Prophase. Chromosomes shorten and thicken and become visible as thick rods, and the nuclear membrane and nucleoli begin to disappear. Each chromosome has two identical threads coiled about each other, each thread being called a chromatid. The two chromatids of each chromosome are known a sister chromatids since they are formed as a result of DNA duplication.

Metaphase. All chromosomes have become lined up all the spindle equator. At this stage of mitosis (and of the cell cycle), they are most tightly condensed. The spindle is composed in part of protein fibers believed to play a role in chromosome movement during the nuclear division. The two chromatids are still attached to each other at the centromere, which becomes associated with spindle fibers.

Anaphase. Attachments between the two sister chromatids of each chromosome break. The two become separate chromosomes.

Telophase. There are two clusters of chromosomes, which decondense. Patches of new membrane fuse to form a new nuclear envelope. Mitosis is completed.

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MATERIAL

Mounted slide of onion (Allium cepa) root tip (l-s)

PROCEDURE

Focus the mounted slide under HPO. Identify and draw the different stages of mitosis. Label the visible structures.

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Exercise No. 11Cellular Reproduction

Name _____________________________ Biology Schedule ________Instructor __________________________ Group No. ______________

Score __________________

Fig. 1.Interphase Fig. 2. Prophase

Fig. 3 Metaphase

Fig. 4. Anaphase Fig. 5. Telophase

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Exercise No. 12Inherited Human Traits and Genetic Problems

INTRODUCTION

The study of human heredity is complicated by the fact that most of the inherited traits in man are influenced by the interaction of several pairs of alleles. There are few physical characteristics however that does show phenotypic variations, which are apparently due to the distinct and can be recognized. Several examples are listed below.

OBJECTIVES

To demonstrate some human hereditary traits and show that every individual (except identical twins) are genetically different from every other individual. This uniqueness with respect to hereditary traits holds true for every sexually reproducing organism.

MATERIALS

None

PROCEDURE

Determine your own phenotype for each trait and record these observations in the table provided at the end of this exercise.

1. Widow’ Peak

In some individual, the hairline comes forward to form a distinct point in the center of the forehead. This point is known as widow’s peak. It results from the expression of a dominant allele (W) whereas a continuous hairline is recessive (w).

2. Free Ear Lobes

Most individuals have free or unattached ear lobes. This characteristic results from a dominant allele (E). Attached ear lobes are recessive (e). You may notice other variation in ear lobes, especially size, if you look at several other members of the class. These variations are due to the expression of other alleles and should not be considered in this exercise.

3. Dimpled Chin

A distinct depression or dimple in the chin results from a dominant allele (C); the presence of a dimple is recessive (c). The depth of the dimple varies and is probably controlled by multiple alleles. Depth should be ignored in this exercise.

4. Convex Nose

A convex bridge of the nose, often called Roman nose, is dominant (N) over a straight or concave nose (n).

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5. Tongue Rolling

Some individual can roll or fold their tongue into a distinct U-shaped when it is extended. Others cannot, regardless of how hard they try. The ability to roll the tongue is dominant (R), inability is recessive (r).

6. Eye Color-Pigmented Iris

The back layer of the iris is normally blue or gray. If nor pigments are deposited in the front layer of the iris, the blue or gray will show through. If pigments results from a homozygous recessive genotype (pp), whereas the presence of pigments results from a dominant allele (P). The variations in the pigment that may be deposited are probably due to multiple alleles and should be ignored.

7. Bent Little Finger

Place your hand flat on the table with muscles relaxed. In some individuals, a dominant allele (B) causes the last joint of the little finger to bend inward towards the fourth finger. If your little fingers are straight, you are homozygous recessive (bb).

8. Mid-Digital Hair

Some individuals have hairs of the second/middle joint of the fingers. The complete absence of hair of the second joint of all fingers is a recessive characteristic (h). The presence of hair is due to the dominant allele (H). It may be necessary to use hand lens to determine this phenotype since the hair may be very short. Also be sure that there is no hair in the middle of any finger before considering yourself recessive for this trait.

RESULTS AND OBSERVATIONS

Indicate your phenotype for the hereditary traits listed in the chart below by checking in the appropriate space. Also indicate your genotype for each of the traits. Record the number of individuals in your class with each of the phenotype.

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Exercise No. 12Inherited Human Traits

Name___________________________________ Biology Schedule _________________ Instructor________________________________Group No. ______________________

Score __________________________

RESULTS AND OBSERVATIONS

No. in class with Hereditary Trait Your Phenotype Your Genotype each Phenotype

1. Widow’s Peak Straight Hair Line

2. Free Ear LobesAttached Hair Lobes

3. Dimpled ChinNondimpled Chin

4. Tongue RollerInability to roll tongue

5. Convex NoseStraight or concave Nose

6. Pigmented IrisNonpigmented Iris

7. Bent little FingerStraight Little Finger

8. Mid-digital HairMid-digital Hair absent

9. Curly hairStraight hair

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QUESTIONS:

Look over the frequencies of the dominant and recessive phenotypes in the class.

A. Questions:

1. Is it true that dominant phenotypes are always the most common in a population? Explain.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

2. Is it possible to determine the genotype, showing a dominant phenotype?A recessive phenotype? Explain.

______________________________________________________________________________________________________________________________________________________________________________________________________________________________

B. Genetics Problems

A. Monohybrid Cross

Complete Dominance. In garden peas, with regards to the height of the tall plant, tall (T) is completely dominant over dwarf (t).

1. A homozygous dwarf pea plant (tt) is pollinated with pollen from a homozygous tall pea plant (TT).

a. What genes will the sperm contain?__________________________________________________________

b. What genes will the egg nuclei contain?__________________________________________________________

c. What will be the phenotype of the F1? The genotype?__________________________________________________________

2. The F1 is self-pollinated.

a. What genes will the sperm contain? The Egg?__________________________________________________________

b. What will be the genotypes of the zygotes formed?__________________________________________________________

c. What will be the phenotype of the plants produced from these zygotes?__________________________________________________________

d. Compare the genotypic rations of these plants produced?

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____________________________________________________________________________________________________________________

Incomplete Dominance. In four o’clock plants, the gene for red flowers (R) Is incompletely or partially dominant over the gene for white flowers (W) so that the heterozygous condition results in pink flowers.

1. What will be the flower color of the offspring of the following crosses:a. RR x WW

_______________________________________________

b. RW x Rw_______________________________________________

c. RW x WW_______________________________________________

2. A four o’clock plant with pink flowers was self-pollinated and 308 plants resulted. Answer the following questions based on this formation.

a. Was the pink flowered plant a pure line or a hybrid?______________________________________________________________________________________________________________

b. How many of the 308 plant will bear red flowers? Pink flowers? White flowers?______________________________________________________________________________________________________________

B. Dihybrid Cross

In pea plants, in addition to height of the plant, cotyledon color and form of the seed was found that yellow cotyledon (Y) is dominant over green (y) and round seed (R) is dominant over wrinkled (r). These genes for the different character are assorting independently of each other. A dihybrid cross is one involving two individuals differing in two pairs of contrasting characters.

1. What are the phenotypes of the following plants and the gametes formed by each:

Table 13.1Genotypes Phenotypes Gametes

a. RRYY

b. RRyy

c. RRYy

d. RrYY

e. RrYy

f. rrYY

g. rryy

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2. If plants (a) and (g) in Table 13.1 were crossed, what is the phenotype of the F1? ____________________________________________________________________________________________________________________________________________

3. If the F1 undergoes self pollination, what would be the genotypes of the offspring? IN what proportion? Answer these questions by filling in the following checkerboard diagram:

4. What are the different phenotypes of the above F2? ________________________________________________________________________________________________________________________________________________________________

5. What is the phenotypic ratio of this F2?_________________________________________________________________________________________________________________________________________________________________