Monera, Algae, Fungi, Plants, and Animals: Key Traits

Monera

Monera are bacteria. They have naked DNA, no defined nucleus or cell organelles, and a complex cell wall. They occupy all kinds of habitats.

Morphology of Bacteria:

  • Cocci: These bacteria have a spherical morphology. They may appear singly or grouped in pairs, or in the form of linear or branched chains.
  • Bacilli: These bacteria have an elongated morphology. They can appear isolated or in associated chains.
  • Curved Bacteria: These bacteria are curved and can be of three types:
    • Vibrios: if they have
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The Respiratory System: How We Breathe and Exchange Gases

The Human Respiratory System: An Overview

The respiratory system is responsible for gas exchange. It captures oxygen from the air and transports it via blood to the body’s cells. It also collects carbon dioxide from the blood to expel it. The airways, which conduct air containing oxygen, include the nostrils, pharynx, larynx, trachea, bronchi, and bronchioles. The lungs facilitate gas exchange between blood and air.

Air Transport and Preparation

Before air reaches the lungs, it must be clean, moist,

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Understanding the Heart: Anatomy, Function, and Circulation

The heart is the engine that drives the blood. It is a hollow, tapered organ located in the thoracic cavity between the lungs. The heart is wrapped by a membrane called the pericardium, and its walls are formed by the heart muscle, or myocardium, which enables the heart to contract and relax.

Heart Structure

The heart is divided into two halves, separated by a partition. Each half has two chambers: an atrium and a ventricle. Each atrium communicates only with its corresponding ventricle. The mitral

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Chromosomal Aberrations, Classification, and Viruses

Chromosomal Aberrations

A chromosomal aberration is a change in the structure or number of chromosomes.


Types of Chromosomal Aberrations

Numerical

Polyploidy

triploidy (3n)

tetraploidy (4n)

Aneuploidy

monosomy (2n-1)

trisomy (2n+1)


Structural

Translocation

Deletion

Duplication

Inversion


*Humans only need one X chromosome; women have two. A condensed X chromosome is known as a Barr Body.*


Syndromes

Down Syndrome – In chromosome 21 (47,xy,+21) – 1 per 800

Edwards Syndrome – In chromosome 18 (47,xy,+13) – 1 per

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Understanding the Internal Environment, Blood, and Circulation

The Internal Environment

The internal environment, through which cells obtain nutrients and eliminate waste products from metabolic reactions, is formed by interstitial plasma. This liquid medium, located in the spaces between cells, must be continually renewed to ensure cells receive adequate nutrients and waste products are removed.

Blood: Composition and Functions

Blood is a viscous fluid with a salty taste that circulates within the circulatory system. It performs several crucial functions:

  • Transports
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Predator-Prey Dynamics, Symbiosis, and Ecosystem Interactions

Predator and Prey Relationships

Predators possess traits or skills that help them catch and kill their prey. Different types of predators have different skills and traits. For example, a cheetah uses its speed to catch prey. On the other hand, tigers have colors that let them blend with the environment so that prey cannot see them easily.

Prey Defenses

Prey generally have some way to protect themselves from being eaten. Different types of organisms protect themselves in different ways:

1. Running Away

When

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