2274 lab practical 1

Once blood clotting is initiated, it usually takes __________ for the fibrin polymer to form.

3-8 minutes

A hematocrit of _______ would be about normal.

45%

What is the correct total WBC count?

5,000-10,000 WBC/μL

Match the percentages to the correct type of leukocyte as we would see it in a healthy individual.

50-70%: neutrophil 25-35%: lymphocyte 4-6%: monocyte 1-3%: eosinophil <1%: basophil

What is the most abundant WBC?

Neutrophils (60-70%)

Calcitonin is released by the parafollicular (C) cells of the thyroid gland when blood calcium levels fall _____ normal levels in the blood

above

Which of the following are considered to be endocrine glands? Select all that apply.

adrenal glands pituitary gland salivary glands sweat glands thyroid gland

When blood sodium (Na+) is too low or blood potassium (K+) is too high, the hormone ____ is released by the zona glomerulosa.

aldosterone

Thyroid hormone secreted by the thyroid gland and epinephrine and norepinephrine secreted by chromaffin cells of the adrenal medulla act to increase

alertness

What problem is most likely the case when a person has a high count of eosinophils?

allergic reaction

Insulin lowers blood glucose levels by

causing skeletal muscle cells to uptake glucose & causing liver cells to uptake glucose.

The _________ is the test to determine bleeding time.

coagulation

The "stress hormone" released by cells of the zona fasciculata is

cortisol

Coagulation culminates in the formation of insoluble threads of

fibrin

Many hours after a meal, alpha (α) cells in the pancreatic islets (islets of Langerhans) secrete

glucagon, which raises blood glucose

The _________ is the test to determine percentage of red blood cells.

hematocrit

Blood cholesterol higher than recommended levels increases the chances of cardiovascular diseases and risks of heart attacks and strokes. Check all the factors that can contribute to high cholesterol levels.

high-fiber diet; lack of exercise; high-cholesterol diet

Excess insulin in the blood can induce

hypoglycemia, hyperglycemia, insulin shock

insulin is a ____ hormone because it acts to lower blood glucose levels

hypoglycemic

What problem is most likely the case when a person has a high count of basophils?

inflammatory processes

After completing a differential white blood cell count on a blood sample, you find a high number of eosinophils. What are some possible causes that could increase the number of eosinophils?

inflammatory reaction; parasitic infection

The specific part of the hemoglobin molecule where oxygen (O2) binds is the

iron (Fe) of the heme

Oxyhemoglobin is formed when oxygen binds to

iron of hemoglobin

lab 3 below

lab 3 below

Which of the following have significant functions for destroying pathogenic microorganisms?

leukocytes

This hormone plays an important role in synchronizing physiological function with the cycle of daylight and darkness.

melatonin

Which leukocyte is the most abundant in a normal differential count?

neutrophil

Which white blood cell has the greatest nuclear variations?

neutrophil

The capillary tube should be sealed _____.

on one side after we put blood in so that the blood will not be pushed out in the centrifuge.

The hormone responsible for milk ejection in lactating mothers is

oxytocin

Which of the following have significant functions mainly during bleeding?

platelets

Which endocrine gland stores hormones synthesized by the hypothalamus?

posterior pituitary

Parathyroid hormone stimulates osteoclasts in bone to ____ blood calcium levels

raise

When testing insulin levels on swimming fish, normoglycemia results in

regular, smooth movements

If thyroid hormones are not released, you can regulate body temperature by _____, which requires a greater use of _____.

shivering; oxygen

When testing insulin levels on swimming fish, hypoglycemia results in

slow, lethargic movements

The hormone responsible for libido and sperm production is

testosterone

With the hematocrit measurement we determine one of the important factors that determine _____.

the oxygen transport capacity of a person's blood

What makes a cell a target of a particular hormone?

the presence of a receptor for that particular hormone

Why does oxygen consumption have to be normalized when comparing two animals?

they differ in muscle mass

The __________ secretes several hormones that stimulate the development of lymphatic organs and regulates development and activity of T cells (white blood cells).

thymus

The ________ secretes a hormone that increases the body's metabolic rate, promotes alertness and quickens reflexes, and stimulates the fetal nervous system.

thyroid gland

The __________ secretes a hormone that increases the body's metabolic rate, promotes alertness and quickens reflexes, and stimulates the fetal nervous system.

thyroid gland

Which two endocrine glands have the closest proximity to each other?

thyroid; parathyroid

Why do you need to hold the slide in a 45 degree angle when making a blood smear?

to ensure the proper thickness of the smear

Why do you need to allow the slide to dry between steps when making a blood smear?

to prevent solutions from simply mixing before staining the cells

Eosinophil numbers typically increase during allergic reactions.

true

The hypothalamus, pineal gland, and pituitary gland are located within the cranial cavity.

true

endocrine glands secrete _____ into the blood

true hormones

When measuring oxygen consumption to measure metabolic activity, you must take into account the ____ of the mice, which is called ____.

weight; normalizing the data

When a blood sample is centrifuged the buffy coat represents the

white blood cell and platelet percentage

overview

Blood is made up of two components: the formed elements and the plasma. Erythrocytes (red blood cells), leukocytes (white blood cells), and thrombocytes (platelets) make up the formed elements. Blood is typically examined with a microscope by staining a peripheral blood smear with Wright's stain. This staining technique is particularly useful for identifying the various types of white blood cells. There are five types of white blood cells that can be categorized as granulocytes or agranulocytes. The granulocytes are so named because of the presence of cytoplasmic granules and the agranulocytes are so named because they do not exhibit cytoplasmic granules. Differentiation of the leukocytes is possible because of the way that the stain is taken up by the various cell types. Neutrophils are a type of white blood cell that have two types of cytoplasmic granules that appear pinkish to light purple when viewed under the microscope. Eosinophils contain cytoplasmic granules that appear dark pink to red when viewed under a microscope. The cytoplasmic granules in the basophils stain a dark purple color and appear to obscure the nucleus. The remaining leukocytes, lymphocytes and monocytes, do not contain cytoplasmic granules. The blood smear can be viewed with a high power lens using a compound light microscope. The slide can be moved side to side in a zig-zag pattern and the white blood cells can be counted. The percentage of each type of white blood cell can then be compared to their normal values. Neutrophils are the most numerous type of white blood cell and they range between 60 and 70% of the total white blood cell count. Lymphocytes range between 25 and 33%, monocytes range between 3 and 8%, and eosinophils range between 2 and 4%. Basophils are the least numerous type of white blood cell and make up less than 0.5% of the total white blood cell count. Abnormal leukocyte counts may be the result of some type of immune response. Increased numbers of one type of leukocyte can indicate the underlying cause for the immune response. For example, increased numbers of neutrophils may indicate a bacterial infection while an increase in the numbers of eosinophils may indicate a parasitic infection.

How is the differential white blood cell count determined?

By counting a set number of white blood cells and noting the percentages of different types of cells