BIO 202: Section 1.3-1.4: Negative Feedback Loop and Blood

What is erythrocytes and their primary functions

Red blood cells that carry oxygen around the body using iron-containing protein called hemoglobin

What is the erythrocytes hematocrit value and how does it differ in males and females

Erythrocytes make up 44% of the total blood volume and is typically higher in males (40-50%) than in females (36-44%)

what are distinguishing features of erythrocytes

It has a reddish-pink color, mature erythrocytes lack a nuclei and most organelles, and it is the most numerous blood cells

What are thrombocytes and their functions

Platelets that are just small cellular fragments that is involved in blood clotting.

What percentage of total blood volume does thrombocytes make up and describe its nuclei

Makes up less than 1% of the total blood volume and lack a nuclei and most organelles

What are leukocytes and their functions

White blood cells that play a role in the immune system. There are two subclasses of leukocytes: granulocytes and agranulocytes based on the presence or absence of visible granules in cytoplasm

What is the percentage of total blood volume of leukocytes and the 2 subclasses of leukocytes

Less than 1% of the total blood volume. Two subclasses are granulocytes (contain visible granulocytes when stained) and agranulocytes (lack visible cytoplasmic granules)

What are granulocytes and the three types of granulocytes

Cells containing cytoplasmic granules that are visible when stained. The three types of granulocytes are neutrophils, eosinophils, and basophils

What are the two dyes that causes granulocytes to stain differently when treated (part of granulocytes in leukocytes)

Hematoxylin (dark purple) and eosin (red)

What is the color of neutrophils and how much of total leukocytes are in the blood (part of granulocytes in leukocytes)

Neutrophils stain a light violet-pink color. They are the most numerous type of leukocyte and make up 60 to 70% of the total leukocytes in the blood

What is another name for neutrophils (part of granulocytes in leukocytes)

Polymorphonucleocytes

What does the neutrophil nucleus look like (part of granulocytes in leukocytes)

They typically have a multilobed nuclei but their nuclei often vary in appearance (which is why they are called polymorphonucleocytes).

What color are eosinophils and how much eosinophils make up the total leukocytes in blood (part of granulocytes in leukocytes)

Eosinophils interact strongly with the red dye: eosin and their granules stain bright red. They are less numerous than neutrophils and account for 4% of the total leukocytes in the blood

What does eosinophils nucleus look like (part of granulocytes in leukocytes)

Their nuclei are segmented into lobes and eosinophil's nuclei tend to be bilobed

What is the function of eosinophils (part of granulocytes in leukocytes)

They play a role in the immune response to infection with parasitic worms and the allergic response

What color are basophils and how much basophils make up the total leukocytes in blood

Basophils take up a dark purple stain: hematoxylin (its a basic dye) and their granules appear dark blue-purple. They are the least numerous of leukocytes, making up fewer than 1% of the total leukocyte count

What is the function of neutrophils (part of granulocytes in leukocytes)

Attracted to the site of any cellular injury: they ingest and destroy bacteria

What is the variation in nucleus shape seen in immature neutrophils called (part of granulocytes in leukocytes)

Band cells: the nucleus of a band cell has a single lobe stretched into a U-shape

What does basophils nucleus look like

They tend to have bilobed nuclei but their nucleus are often obscured by their dark granules

What are the two types of agranulocytes

Lymphocytes and monocytes

What is the function of basophils

They are primarily involved in the allergic response

Describe lymphocytes, their color, and nuclei

Lymphocytes tend to be smaller than granulocytes and have a large, spherical nuclei that are surrounded by a rim of light blue-purple cytoplasm

How much of the total leukocyte count does lymphocytes make up

They are the second most numerous type of leukocyte, making up 20 to 25% of the total leukocyte count

What are the two population of lymphocytes and their functions

B lymphocytes: produce proteins called antibodies that bind foreign glycoproteins called antigens. T lymphocytes: enhances other aspects of the immune response, destroying cancer cells, and destroying cells infected with viruses

Describe monocytes and their nucleus

Monocytes are the largest of the leukocytes and have a U-shaped or horshoe-shaped nuclei with light blue or light purple cytoplasm.

How much of the total leukocyte does monocyte account for

They are the third most numerous type of leukocyte, accounting for 3 to 8% of the total

What is the function of monocytes

They exit the blood to mature into cells called macrophages, which are very active phagocytes. Phagocytes engulf or eat bacteria or other foreign cel

What is the stimulus for secretion and some variables that can cause it

Generally a disturbance in the homeostasis of a particular physiologic variable, such as blood pressure, concentration of glucose in blood, and body temperature

What is the hormone’s response when a disturbance in homeostasis happens and there is a stimulus for secretion

To act on distant target cells to cause changes that restore the variable to its normal range

What happens when homeostasis is restored and what is it called

The activity of the glands and concentration of the hormone declines called negative feedback loop

What does negative feedback loop ensure

When a hormone level is high, its secretions remain low. If a hormone’s secretion drops, then a stimulating hormone’s secretion rises, which stimulates an endocrine organ to secrete more hormone

What is an example of negative feedback loop regarding concentration of glucose in the blood falling

Concentration of glucose in the blood falls → the pancreas releases glucagon → the level of the hormone glucagon in the blood rises → the hormone glucagon causes glycogenolysis by the liver → the concentration of glucose in the blood rises → the level of the hormone glucagon in the blood decreases

What are the two main components of whole blood

Plasma: the fluid portion of blood accounting for 55% of the blood volume (consist of water, proteins, other solutes like nutrition and ions)
Formed elements: the cellular portion of blood accounting for 45% of the blood volume (there are three classes: erythrocytes, thrombocytes, and leukocytes)

What is the three classes of formed elements in blood

Erythrocytes (red blood cells), Thrombocytes (platelets), Leukocytes (white blood cells)