Human Physiology: Nephrons, Cells, Nerves and Hormones
Urine Formation
Nephrons are small structures that filter the blood to form urine. Each consists of a glomerulus ...
Nutrients
Nutrients are chemical substances that contain energy and are used by cells to carry out their vital functions.
Eukaryotic Cells
Plasma membrane is an envelope or layer that consists mainly of proteins and lipids.
Cytoplasm is the space between the plasma membrane and the nucleus.
Types: animal and plant.
Mitosis and Cytokinesis
Mitosis is cell division: prophase, metaphase, anaphase, telophase ...
Cytokinesis
Accessory Glands
Accessory (annex) glands are connected with the digestive tract.
Energy Conversions
- 1 kcal energy value = 1000 calories
- 1 kcal = 4.184 kJ
- 1 kJ = 0.239 kcal
Eating Disorders
Anorexia is a psychiatric disorder characterized by dissatisfaction with physical appearance; it can lead to osteoporosis.
Bulimia is a psychiatric disorder in which people suffer episodes of binge eating and often vomiting; they feel a gripping fear of gaining weight ...
Neurons
Neurons: three parts are distinguished. The cell body is the part that contains the nucleus and most of the cytoplasm.
Dendrites are short ramifications emanating from the cell body of the neuron.
The axon is the longest prolongation and has fewer branches than dendrites.
Nervous System
The peripheral nervous system connects the central nervous system with the organs of sense.
- Sensory nerves are formed by sensory neurons and are responsible for transmitting information from the sense organs to the central nervous system.
- Motor nerves are formed by motor neurons and transmit nerve impulses from the central nervous system to the various organs of the body where a response must occur.
Alzheimer's is a serious neurological disorder due to premature loss of neurons and the alteration of communication between them.
Voluntary and Reflex Actions
Voluntary acts are those we decide to carry out of our own volition.
Reflex actions are involuntary responses that are processed and coordinated in the spinal cord.
Endocrine System
The endocrine system is responsible for carrying out hormonal responses; secretion occurs in response to a stimulus.
It is constituted by a set of organs: endocrine glands that produce hormones.
It is controlled by the hypothalamus, a cluster of neurons located at the base of the brain.