Search Results

Cellular slime mold life cycle Animation

By: HWC, Views: 1960

Life cycle of Dictyostelium discoideum, a cellular slime mold Animation. Amoeba-like slime mold cells live in the soil, where they feed on bacteria. The free-living cells grow and reproduce by mitosis. When food dwindles, the amoebas stream toward one another in response to a chemical...

Oxygen transport: association and dissociation & Factors that affect hemoglobin's saturation with O2

By: HWC, Views: 7668

• The production of oxyhemoglobin can be illustrated through the following reaction: 02 + Hb-H --) Hb-02 + H+ • This equation represents the binding of oxygen to the iron ions in heme groups in hemoglobin molecules. • Oxygen binding or loading occurs at the lungs • The dissociatio...

Definition of heart rate

By: HWC, Views: 7857

• Heart rate is determined by the rate of depolarizations of the sinoatrial (SA) node. • Cardiac output is directly proportional to heart rate, the greater the heart rate the greater the cardiac output. • Changes in heart rate are associated with exercise, stress or injury. Nervous ...

Glycolysis - Introduction to ATP and the burning of sugar

By: HWC, Views: 7845

Do you use sugar with your coffee or tea? Or do you occasionally drink a sport or soft drink? As millions of people do each day, they obtain energy from the sugar added or contained in these drinks. How can we understand this concept of energy within a sugar molecule? Let's take a tablespoon ...

Olfaction. or the sense of smell

By: HWC, Views: 5147

Do you ever wonder how you can distinguish thousands of different odors? Olfaction. or the sense of smell, is used by all mammals to navigate, find food, and even find mates. We have millions of olfactory receptors for smelling in our nose. These receptor neurons bind water-soluble or volatil...

Primary Active Transport - electrochemical gradient and ion transport / water movement

By: HWC, Views: 7845

Energy derived from ATP changes the shape of a transporter protein which pumps a substance across a plasma membrane against its concentration gradient An electrochemical gradient is a gradient of electrochemical potential, usually for an ion that can move across a membrane. The gradient consis...

Evolutionary tree of life Animation

By: HWC, Views: 1384

An evolutionary tree of life that reflects mainstream thinking about the connections among major lineages (bya = billions of years ago, mya = millions of years ago). By about 3.8 billion years ago, chemical and molecular evolution had produced the first living cells. The first major divergenc...

Proteins

By: HWC, Views: 6770

Living things must accomplish a great number of tasks just to get through a day, and these tasks are accomplished by a diverse range of biological molecules. In the range of tasks that molecules accomplish, however, proteins reign supreme. Almost every chemical reaction that takes place in living...

Methods that regulate pH

By: HWC, Views: 7884

• The blood flow redistributes fluids that have different pH values between body regions. • The regulation of the blood pH is important to maintain homeostasis. • Blood pH is regulated by: • Chemical buffers. • The respiratory system. • The urinary system. • All thes...