The Human Brain: Structure, Function, and Clinical Significance

The Hemispheres of the Cerebrum

Left and Right Hemispheres

The cerebrum is divided into two hemispheres, the left and right hemispheres.

Neural Cortex

The gray matter on the surface of the cerebrum is called the neural cortex.

Functions of the Cerebrum

True: Conscious thoughts, sensation, intellect, intelligence, rationalization, and complex movement all originate in the cerebrum.

True: The highest level of information processing occurs in the cerebrum.

True: The cerebrum controls higher mental functions.

Read More

Hormonal Regulation, Renal Physiology, and Reproductive Health: An In-Depth Guide

Hormonal Regulation of Renal Sodium Reabsorption

Question: Mention two hormones that would increase renal Na+ reabsorption. What are their effects and mechanisms of action? Which segments of the renal tubules do they affect?

Answer:

Two hormones that are secreted to increase Na+ reabsorption are:

1. Aldosterone

Aldosterone stimulates Na+ reabsorption in principal cells of the distal convoluted tubule (DCT) and cortical collecting duct (CCD). It increases Na+ reabsorption in exchange for K+ secretion.

Read More

Human Biology and Nutrition

Sense Organs

Hearing

Hearing consists of three parts: the external ear, middle ear, and inner ear.

External Ear

This is formed by the pinna, the ear canal, and the eardrum.

  • It is in charge of collecting and transmitting sound waves into the middle ear.
  • The ear canal contains small hairs and wax-producing glands that are responsible for protecting the inside.
  • The eardrum is a membrane that separates the outer ear and middle ear.

Middle Ear

This is formed by the tympanic cavity, which contains three holes.

Read More

Understanding Cells and Tissues: A Comprehensive Overview

Chapter 3: Exploring the Cell

What is a Cell?

The cell is the fundamental structural and functional unit of the body. It is the smallest living unit.

Three Main Regions of a Cell

  • Cell Membrane: The outer boundary of the cell.
  • Cytoplasm: Includes the cytosol (watery fluid) and organelles.
  • Nucleus: The control center of the cell.

Structure of the Cell Membrane

The cell membrane is a phospholipid bilayer, composed of two layers of phospholipids. Embedded within this bilayer are proteins and cholesterol. Carbohydrates

Read More

The Immune System, HIV/AIDS, and the Respiratory System: A Comprehensive Overview

4 Phagocytic Leucocytes and Pathogen Ingestion

Phagocytes, found in the blood and body tissues, play a crucial role in the immune system. They identify and engulf pathogens through endocytosis. Lysosomes, enzymes within phagocytes, then break down these pathogens. Phagocytes can move through capillary pores, allowing them to ingest pathogens both in the bloodstream and within tissues.

5 Antigens vs. Antibodies

Antibodies are proteins that defend the body against pathogens. They bind to antigens, foreign

Read More

Fetal Development: Cognitive Functioning and Learning

Fetal Development: Cognitive Functioning and Fetal Learning

Prenatal Development

The case for 9 months in a pattern that is not uniform. Throughout this period, changes of varying intensity and importance occur. The periods during which prenatal life is conventionally divided are: conception, zygote (development until the 2nd week), embryo (3rd-8th week), and fetus (9th to 38th week).

Phases of Development

Conception

Every 28 days, an egg leaves the ovary and travels to the uterus through the fallopian

Read More