CELL Is The Fundamental Structural

CELL is the fundamental structural and functional unit of all living organism and anything less than a complete cell has no independent existence.

In 1665, Robert Hooke observed a thin section of cork under a compound microscope, noticed a honey-comb like compartments. He coined the term “Cell”.

In 1674, Anton Von Leeuwenhoek first saw and describe the living cell.

Later, in 1831, Robert Brown discovered the nucleus in the root cells of orchids.

The invention of the microscope & its improvement leading to the electron microscope revealed all the structural details of the cell.

CELL THEORY

In 1838, Matthias Schleiden found that all the plant cells have essentially similar structure and have a cell wall.

In 1839, Theodore Schwann studied different types of animal cells and reported that cells had a thin outer layer which is today known as the ‘plasma membrane’. He also concluded that the presence of cell wall is a unique character of the plant cells. On the basis of this Schwann proposed the hypothesis that the bodies of animals & plants are composed of cells & products of cells.

Schleiden and Schwann together formulated the cell theory. This theory, however, didn’t explain as to how new cells were formed.

In 1855, Rudolf Virchow first explained that the cells divided and new cells are formed from pre-existing cells. He modified the hypothesis of Schleiden and Schwann to give the cell theory a final shape.

Cell theory as understood today is:-

• All living organisms are composed of cells and cell products.
• All cells arise from pre-existing cells.

CELL ORGANELLES

Eukaryotic cell (Plant and Animal) consists of following cell organelles:­­­–

• Cell membrane
• Cell wall
• Endoplasmic Reticulum
• Golgi bodies
• Nucleus
• Lysosomes
• Vacuoles
• Mitochondria
• Plastids
• Ribosomes
• Cilia & Flagella

CELL MEMBRANE – It is the outermost (in the animal cell including human cell) and inner to the cell wall (in plant cells), a thin, transparent, elastic & semi-permeable membrane. It helps in exchange of materials between cytoplasm and extracellular fluid.

CELL WALL – It is the outermost layer, present in the plant cell, bacteria & in algae. It gives shape to the cell, protects the cell from mechanical damage and infection, helps in cell-to-cell interaction & provides the barrier to undesirable macromolecules.

ENDOPLASMIC RETICULUM – Endoplasmic Reticulum (ER) is a network of tiny tubular structures scattered in the cytoplasm. The ER bearing Ribosomes on their surface is called Rough Endoplasmic Reticulum (RER). In the absence of Ribosomes, they appear smooth and are called Smooth Endoplasmic Reticulum (SER).RER is actively involved in protein synthesis and secretion. The SER is the major site for lipid synthesis & lipid-like steroidal hormones.

GOLGI BODIES – They consist of many flat, disc-shaped sacs or cisternae of 0.5 1 micron diameters, stacked parallel to each other. It involved in cell secretion, the formation of hormones, biosynthesis of glycolipids & glycoproteins.

NUCLEUS – The nucleus, also called the director of the cell, is the most important part of the cell which directs and controls all the cellular functions.

LYSOSOMES – These are vesicular structures of the cytoplasm which are involved in intra-cellular digestive activities; contain all types of hydrolytic enzymes, also known as the suicidal bag of the cell.

VACUOLES – These are the membrane-bound space found in the cytoplasm, contains water, sap, excretory product and other materials not useful to the cell. It stores water, nutrients and minerals, helps in growth and elongation of cells.

MITOCHONDRIA – It is a double membrane-bound structure with the outer membrane and inner membrane dividing its lumen into two compartments. They are called powerhouses of the cell as these are sites of ATP formation.

PLASTIDS – These are found in plant cells, are of 3 types – chloroplasts, chromoplasts & leucoplasts. The chloroplast contains chlorophyll, responsible for trapping light energy for photosynthesis. Chromoplasts contain carotene, xanthophylls & other pigments. Leucoplasts are colorless plastids. These are absent in animal or human cell

RIBOSOMES – These are granular structures, composed of RNA and proteins & are surrounded by any membrane. The eukaryotic Ribosomes are the 80S while prokaryotic Ribosomes are 70S. These are the sites of protein synthesis.

CILIA & FLAGELLA – Cilia & Flagella are microscopic, hair or thread-like motile structures present extra-cellularly but originate intra-cellularly and help in locomotion, feeding, circulation etc.

ANATOMY & PHYSIOLOGY INTRODUCTION

INTRODUCTION TO ANATOMY & PHYSIOLOGY

Anatomy & physiology plays the vital role in medical science, without the knowledge of Anatomy and Physiology there is no independent existence of other areas of study in medical science. Human anatomy is the branch of science which deals with the study of the internal and external structure of the human body whereas Physiology is defined as the branch of science that deals with the study of normal functions of the Human body.

Andreas Vesalius (1514-1564) for his best-known word ‘fabrica humani corporis’ in which he incorporated both anatomy and physiology, is known as the father of modern Anatomy and William Harvey (1578-1657), who discovered the system of blood circulation is regarded as the father of modern Physiology.

What Is Anatomy and Physiology?

Anatomy : is the study of the structure and relationship between body parts.

Physiology : is the study of the function of body parts and the body as a whole. Some specializations within each of these sciences follow:

Gross (macroscopic) anatomy : is the study of body parts visible to the naked eye, such as the heart or bones.

Histology : is the study of tissues at the microscopic level.

Cytology : is the study of cells at the microscopic level.

Neurophysiology : is the study of how the nervous system functions.

Organizations of living systems

Living systems can be defined from various perspectives, from the broad (looking at the entire earth) to the minute (individual atoms). Each perspective provides information about how or why a living system functions:

• At the chemical level, atoms, molecules (combinations of atoms), and the chemical bonds between atoms provide the framework upon which all living activity is based.

• The cell is the smallest unit of life. Organelles within the cell are specialized bodies performing specific cellular functions. Cells themselves may be specialized. Thus, there are nerve cells, bone cells, and muscle cells.

• A tissue is a group of similar cells performing a common function. Muscle tissue, for example, consists of muscle cells.

• An organ is a group of different kinds of tissues working together to perform a particular activity. The heart is an organ composed of muscle, nervous, connective, and epithelial tissues.

• An organ system is two or more organs working together to accomplish a particular task. The digestive system, for example, involves the coordinated activities of many organs, including the mouth, stomach, small and large intestines, pancreas, and liver.

• An organism is a system possessing the characteristics of living things—the ability to obtain and process energy, the ability to respond to environmental changes, and the ability to reproduce.

COMMONLY USED TERMINOLOGIES 

• • Anterior or Ventral – Front side of the body
  • Posterior or Dorsal – Back side of the body
  • Superior or Cranial – Towards head
  • Inferior or Caudal – Towards feet
  • Medial – In the Middle

• Lateral – Away from the mid-point
• Proximal – Starting point
• Distal – Ending point
• Superficial – Close to the skin or Towards surface of the body.
• Deep – Away from skin or Away from the surface of the body.
• Ipsilateral – On the same side of the body as another structure
• Contralateral – On the opposite side of the body as another structure.
• Invagination – Projection inside
• Evagination – Projection outside

VARIOUS BODY POSITIONS

• Anatomical position – When a person is standing straight with the eyes looking forward, both the arms the side of the body, palms facing forwards, both feet together.
• Supine position – When a person is lying on his/her back, arms by the side, palms facing upwards and feet put together.
• Prone position – Person lying on his/her face, chest and abdomen.
• Erect position – Person standing straight.
• Lithotomy position – Person lying on her back with legs up and feet supported in straps, mostly used during delivery of the baby.

VARIOUS BODY PLANES

• Median/ Midsagittal plane – A plane passing through the center of the body dividing it into two equal right and left halves is the median or midsagittal plane.
• Coronal/ Frontal plane – A plane which divides the body into anterior and posterior halves is called the coronal plane.
• Transverse/ Axial plane – A plane which divides the body into upper and lower parts is called a transverse plane.
• Sagittal/ Lateral plane – A plane which divides the body into two unequal left and right halves is called the sagittal plane.

BODY CAVITY 

It is divided into two parts 

• Anterior/Ventral Cavity – It is divided into the Thoracic cavity, Abdominal cavity, and the Pelvic cavity.
• Posterior/Dorsal Cavity – It is divided into Cranial Cavity and the Spinal Cavity.

Obstetrical Emergencies and their Prevention

List of Obstetrical Emergencies and their Prevention

Health problems that pose a threat to the life of pregnant women and their fetus are referred to as obstetrical emergencies. It can occur at any time during pregnancy, labor, and or birth. When obstetrical emergencies occur, hospital care is needed; this is because there may be a need for expert intervention and long period stay at the clinic. In the event that you noticed that you and your fetus are in danger, make sure you get in touch with your doctor, midwife, or hospital for urgent care. Here we have a list of seven obstetrical emergencies and ways to prevent them.

ECTOPIC PREGNANCY

This occurs when fertilized eggs implant itself in the fallopian tube instead of the normal place, which is the uterine wall. On the off chance that pregnancy is not terminated at an early stage, this could lead to rupture of the fallopian tube, leading to internal bleeding and potentially permanent infertility.

It can be prevented by reducing the number of sexual partners, using protection such as condoms during intercourse in other to avoid sexually transmitted diseases, and also it is good to avoid smoking before getting pregnant.

PLACENTAL ABRUPTION

This is also referred to as placenta abruption. It occurs as a result of premature separation of the placenta from the uterus. This result in bleeding and contractions; in the event that 50% of the placenta is separated, the fetus and mother are in danger.

It can be prevented by avoiding all substances such as cigarettes, alcohol, medicines (except those that are prescribed by your doctors) and illegal drugs during pregnancy.

PLACENTA PREVIA

Placenta previa occurs when the placenta binds to the mouth of the uterus and partially or completely blocks the cervix. This condition can also be referred to as low-lying placenta. Placenta previa can lead to premature bleeding and possible bleeding after delivery.

It can be prevented by staying away from activities that can cause contractions such as having sex, douching, using tampons, or engaging in activities that can increase your risk of bleeding, such as running, squatting, and jumping among others.

PREECLAMPSIA / ECLAMPSIA

This condition can lead to severe edema, and it can affect the function of the kidneys and liver. In the United States, it can affect about 5% of all pregnancies. In case it metamorphosis to eclampsia, eclampsia is potentially fatal for both mother and child.

This can be prevented by reducing salt intake, drinking 6 to 8 glasses of water per day. Reducing the consumption of fried and junk food, regular exercises, avoid drinking alcohol, and avoid beverages containing caffeine.

PREMATURE RUPTURE OF MEMBRANES (PROM)

This is the breaking of the amniotic fluid before the onset of contraction or labor. PROM is considered an emergency if the break occurs before thirty-seven weeks and results in significant leakage of amniotic fluid and infection of the amniotic sac. Staying away from cigarettes is one of the possible ways to prevent the occurrence of PROM.

Miscarriage 

This is the loss of a baby before 20 weeks of delivery. Miscarriage cannot be stopped when it starts. It is advisable to take good care of the abdomen while pregnant. Also staying away from the strenuous activity with a high risk of injury, healthy eating, manage stress is one of the ways to prevent miscarriage.

Headaches

Cephalalgias can occur during the first trimester when the body experiences an increase in hormones and an increase in blood volume. These headaches can be exacerbated by stress, poor posture, or changes in vision. 

The best way to prevent the occurrence of headache is by avoiding tension, and this can be achieved by following the tips listed below

• Maintain good posture
• Get plenty of rest
• Exercise
• Eat well-balanced meals

Neurological Emergencies and their Prevention

Top 7 Psychological/Psychiatric Emergencies and Their Prevention

Psychiatric emergencies are an area little-known by the general population, which is very well dealt with -and very seriously- by hospital institutions. Unlike organic emergencies, when it comes to the mind the consequences can be lethal not only for those who suffer it but also for the people around them.

It is difficult to address these issues with family because there is a stigma and lack of culture when it comes to psychiatric disorders. Many are afraid, so they do not want to talk about it with their family; however, this is the worst mistake. Let’s talk about the most frequent emergencies:

• The Suicidal Patient

Suicide statistics have risen in the last decade to unthinkable levels. It is a serious problem that often occupies emergency rooms.

It is easy to “guess” what kind of patient may or may not be suicidal. Not just the way he acts or thinks, but also the way he looks. The most important thing is to learn to recognize these characteristics that are called risk factors.

The most frequent are isolation, feelings of deep sadness, inability to maintain social relationships, psychological stress (loss of a job, relationship, etc.), alcohol and substance abuse.

• Depressive Syndrome

The prevalence of depression is also high, especially in women. The worst part is that only half of patients with this disorder have adequate treatment.

The worst thing is to underestimate the capacity of depression and its symptoms. Deep sadness, apathy, loss of interest, appetite and sleep disorders are some of the most frequent manifestations.

Depression can lead to suicide, but also to lethal behaviors on people close to you. In addition, it leads to chronic organic damage, so it can be lethal.

• Panic Attack

Diagnosis can be complicated because the patient may be showing symptoms of other diseases. However, most often there is a triggering phobia (an exaggerated and unreal fear) and many physical symptoms such as tachycardia, headache, profuse sweating, chest pain, etc.

• Acute Psychosis

The central problem of acute psychosis is the disconnection with reality; however, the patient may enter two different states of exacerbation: mania and depression. Either of the two poses an enormous risk to the health of the patient and his or her family since it can enter into aggressive crises with hallucinations that force the patient to “attack”.

• Psycho pharmaco-toxicology

The drugs used in psychiatry are very different from conventional ones. They have powerful adverse effects that are difficult to control. The doctors’ thinking is: “Better with these side effects than with the base pathology”. However, it may involve the death of the patient (from myocardial infarctions) or suicidal behaviors.

• Delirium

Sometimes there is an organic alteration in the brain that causes psychiatric symptoms with alterations in psychomotor behavior. They usually have major cognitive disorders, so they end up reacting aggressively to anything that passes through their environment.

Although the exacerbations are ” temporary “, the ability to self-injury and injure others is quite high.

• Somatomorphic Disorders

The psychiatric emergency also includes those patients who are not ill but who – consciously or unconsciously – manifest symptoms. They may have a very high fever, severe dyspnea, or even a feeling of imminent death from a heart attack, although organically nothing is happening, everything is in the mind.

How to prevent mental health?

The most important thing will always be to be informed. Learn about what’s in the world and don’t underestimate anything we see daily. Mental Health is the most ignored area of medicine, and perhaps the most important of all.

Having good mental health helps you recover faster, get out of the hospital faster, get sick less, etc. There are many benefits presented by science. The ideal in prevention is to perform the “primary” mode that tries to prevent the onset of any psychiatric disease since for most of them there is no cure but “control” therapies.