BSC1005-2

BSC 1005

TEST UNIT II

JUNE 22, 2007

Lecture I:

Body Function, Survival, and the Steady State

Physiology

Physiology is a branch of biology that deals with function and coordinated activities of cells, tissues, and organs.
Physiological Systems function as body communication and different ways to maintain homeostasis within the body.

Homeostasis

The purpose of homeostasis is to regulate the internal environment and maintain a stable, constant condition.
Main characteristic of living things.
Most disease results from disturbance of homeostasis in the body.

Important Body Facts

There are 75 billion cells in the human body.
200 different types of cells coexist in our body.
Four different types of tissue exist in the body

-epithelial (skin tissue), muscle (arm movement), nervous (neurons), and connective tissue (connects parts together).

Stem Cells

Embryonic Stem Cells are important for research because of their ability to become all different cell types, if they are given the correct signals to do so.
Cell Differentiation is when signals are sent to cells, and depending on that signal, the stem cells become whatever the surrounding cells are.

-the cell can change dramatically, but the genetic material still stays the same, with few exceptions.

Lecture 2:

Circulatory and Respiratory Systems

Respiratory System

In conjunction with the Circulatory System, delivers Oxygen (O₂) to every cell

and rids the cell of Carbon Dioxide (CO₂) waste.

Removes the requirements for each cell to be in contact with an Oxygen source.

How Do We Breathe?

Each lung is contained within a plural membrane (an enclosing tissue made of lipids which acts as a barrier around the lung).
The rib cage and diaphragm form a thoracic cavity which is also lined with a membrane.
The rib cage rises, the diaphragm flattens, and causes the thoracic cavity to expand.
This changes the air pressure in the lungs to that lower than atmospheric pressure, and vice versa.

Nose Functions

Air is cleaned, warmed, and humidified.

-The nose is lined with small hairs (cilia) and mucus, which catch bacteria and dust particles.

-A network of blood vessels lies just below the nasal membrane that warms air (which is why we get nose bleeds easily).

-The mucus humidifies the air which allows gas transfer.

Air then moves through the trachea, which also contain cilia to filter air, and then move through bronchioles to the alveoli in the lungs, where gas transfer takes place.

Alveoli

Alveoli are only one cell thick (compared to the three million cells that make up the lungs).
Capillaries surround each cluster of alveoli.
Alveoli remain open due to surfactant (a lipoprotein that reduces surface tension to keep alveoli open reacts at birth so lungs will not collapse).
This process is external respiration (cigarettes cause damage through filling alveoli with black tar, causing the lungs to be unable to fill alveoli with air and create more damaged alveoli).
The process that begins at the nose and ends at the alveoli is called Respiration.

Two Types of Respiration

External Respiration-the exchange of Oxygen and Carbon Dioxide between moist respiratory surfaces and blood.
Internal Respiration-the exchange of Oxygen and Carbon Dioxide between blood and cells.

Circulatory System Function

To transport nutrients, dissolved gasses, wastes, salts, proteins, and phagocytes (white blood cells) throughout the body.

Blood Components

Eight percent of our lean body mass consists of blood.
The normal male body has 5.5 L of blood, the normal female has 5.0 L of blood.
Blood is comprised of plasma (similar to salt water, contains water, ions, and proteins), and cells (red blood cells, white blood cells and platelets).

Blood Pressure

Blood pressure is the heart’s pumping action and amount of vasoconstriction.
Systolic Pressure: the peak of pressure, when ventricles contract
Diastolic Pressure: the low point of pressure, when ventricles relax
Blood pressure is the Systolic pressure over the Diastolic pressure.

Arteries

Arteries are made of very elastic tissue and some muscle.
The heart contracts and blood is forced in, causing arteries to dilate.
The heart relaxes, and arteries recoil pushing the blood through the arteries.
The arteries are connected to arterioles, which leads to capillaries.



	BSC 1005 BSC 1005 TEST UNIT II JUNE 22, 2007 Lecture I: Body Function, Survival, and the Steady State Physiology Physiology is a branch of biology that deals with function and coordinated activities of cells, tissues, and organs. Physiological Systems function as body communication and different ways to maintain homeostasis within the body. Homeostasis The purpose of homeostasis is to regulate the internal environment and maintain a stable, constant condition. Main characteristic of living things. Most disease results from disturbance of homeostasis in the body. Important Body Facts There are 75 billion cells in the human body. 200 different types of cells coexist in our body. Four different types of tissue exist in the body -epithelial (skin tissue), muscle (arm movement), nervous (neurons), and connective tissue (connects parts together). Stem Cells Embryonic Stem Cells are important for research because of their ability to become all different cell types, if they are given the correct signals to do so. Cell Differentiation is when signals are sent to cells, and depending on that signal, the stem cells become whatever the surrounding cells are. -the cell can change dramatically, but the genetic material still stays the same, with few exceptions. Lecture 2: Circulatory and Respiratory Systems Respiratory System In conjunction with the Circulatory System, delivers Oxygen (O₂) to every cell and rids the cell of Carbon Dioxide (CO₂) waste. Removes the requirements for each cell to be in contact with an Oxygen source. How Do We Breathe? Each lung is contained within a plural membrane (an enclosing tissue made of lipids which acts as a barrier around the lung). The rib cage and diaphragm form a thoracic cavity which is also lined with a membrane. The rib cage rises, the diaphragm flattens, and causes the thoracic cavity to expand. This changes the air pressure in the lungs to that lower than atmospheric pressure, and vice versa. Nose Functions Air is cleaned, warmed, and humidified. -The nose is lined with small hairs (cilia) and mucus, which catch bacteria and dust particles. -A network of blood vessels lies just below the nasal membrane that warms air (which is why we get nose bleeds easily). -The mucus humidifies the air which allows gas transfer. Air then moves through the trachea, which also contain cilia to filter air, and then move through bronchioles to the alveoli in the lungs, where gas transfer takes place. Alveoli Alveoli are only one cell thick (compared to the three million cells that make up the lungs). Capillaries surround each cluster of alveoli. Alveoli remain open due to surfactant (a lipoprotein that reduces surface tension to keep alveoli open reacts at birth so lungs will not collapse). This process is external respiration (cigarettes cause damage through filling alveoli with black tar, causing the lungs to be unable to fill alveoli with air and create more damaged alveoli). The process that begins at the nose and ends at the alveoli is called Respiration. Two Types of Respiration External Respiration-the exchange of Oxygen and Carbon Dioxide between moist respiratory surfaces and blood. Internal Respiration-the exchange of Oxygen and Carbon Dioxide between blood and cells. Circulatory System Function To transport nutrients, dissolved gasses, wastes, salts, proteins, and phagocytes (white blood cells) throughout the body. Blood Components Eight percent of our lean body mass consists of blood. The normal male body has 5.5 L of blood, the normal female has 5.0 L of blood. Blood is comprised of plasma (similar to salt water, contains water, ions, and proteins), and cells (red blood cells, white blood cells and platelets). Blood Pressure Blood pressure is the heart’s pumping action and amount of vasoconstriction. Systolic Pressure: the peak of pressure, when ventricles contract Diastolic Pressure: the low point of pressure, when ventricles relax Blood pressure is the Systolic pressure over the Diastolic pressure. Arteries Arteries are made of very elastic tissue and some muscle. The heart contracts and blood is forced in, causing arteries to dilate. The heart relaxes, and arteries recoil pushing the blood through the arteries. The arteries are connected to arterioles, which leads to capillaries.