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Summary of female reproductive cycle days 1-28

By: HWC, Views: 8147

■ The first five days of the cycle include the menstrual phase. ■ Progesterone and estrogen levels are low. ■ Menses occurs. ■ GnRH pulses more frequently promoting FSH and LH levels to rise. ■ Primary follicles are stimulated to develop. ■ Days five through thirteen consist o...

Basic rhythm - control centers in medulla oblongata, spirograph and normal tidal cycle

By: HWC, Views: 7577

• Normal ventilation is rhythmic and involves continuous cycles of inspiration and expiration. • Various regions of the brain closely regulate this rhythmic pattern of ventilation. • The rhythmicity area in the medulla regulates the basic rhythm of ventilation. • The medullary rhy...

Apicomplexan life cycle Animation

By: HWC, Views: 2039

Malaria is caused by the sporozoan, Plasmodium. It is transferred to humans by mosquitoes. When an infected mosquito feeds, infective sporozoites move from her salivary glands into the human body. The bloodstream carries the sporozoites to the liver. Here, they reproduce asexually and...

Contraction cycle of a sarcomere

By: HWC, Views: 8178

• A single nervous signal releases Ca2+ ions into the sarcoplasm and initiates the contraction cycle. step 1. ATP hydrolysis • ATP provides the to move myosin molecules back into the energized configuration necessary to perform the power stroke. Step 2. Crossbridge attachment • Myosin...

Green alga life cycle Animation

By: HWC, Views: 2346

Chlamydomonas zoospores are haploid flagellated cells. As long as conditions are favorable, these cells reproduce asexually. As many as sixteen cells may form by mitosis within a parent cell. Daughter cells escape when the cell wall ruptures. When conditions become less favorable, the...

How Hemoglobin Picks Up and Delivers Oxygen

By: HWC, Views: 7027

All of the cells in our bodies require oxygen (02) for survival and must release carbon dioxide (CO2) as a waste product. The respiratory and circulatory systems work together as delivery systems for these gases. The lungs exchange these gases between the environment and the bloodstream. The bloo...

Conduction of action potentials

By: HWC, Views: 7884

• Action potentials must be rapidly conducted over long distances in order for the nervous system to communicate with other cells. • Propagation of an action potential uses processes similar to those that generate the potential at the trigger zone. • a When a graded potential reaches ...

Phases of the ovarian cycle

By: HWC, Views: 8061

• The ovarian cycle is a monthly sequence of events, consisting of three phases: • Preovulatory • Ovulatory • Post ovulatory Preovulatory phase • prior to ovulation: Primary follicles develop into secondary follicles. • Follicular cells surrounding the primary oocyte In...

Heart sounds

By: HWC, Views: 7605

During a normal, healthy heartbeat, or what we call a cardiac cycle, the top two chambers of the heart, called the atria, contract simultaneously. Then, as they relax, the bottom two chambers, called the ventricles, contract. This explains what happens during a cardiac cycle, but what it doesn't ...