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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Living Organisms: Characteristics, Classification & Kingdoms

Characteristics of Living Organisms

  • Movement: Change of position or place by an action.

  • Respiration: Chemical reactions in cells that break down nutrient molecules and release energy for metabolism.

  • Sensitivity: Capacity to react to stimuli presented by the environment.

  • Growth: Permanent increase in size and dry mass.

  • Reproduction: Processes that make more of the same kind of organism.

  • Excretion: Removal of waste products.

  • Nutrition: Taking in of materials for energy, growth, and development.

Viruses

  • Viruses
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Photosynthesis in Plants: Process and Factors

Plants use water from the soil, carbon dioxide from the air, and energy from sunlight to make carbohydrates & oxygen.

Green plants absorb light energy using chlorophyll in their leaves. They use it to react carbon dioxide with water to make a sugar called glucose. The glucose is used in respiration, or converted into starch and stored. Oxygen is produced as a by-product.

Balanced Equation for Photosynthesis

6CO2 + 6H2O light/(chlorophyll) C6H12O6 + 6O2

Investigating the Necessity for Chlorophyll,

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Nervous and Endocrine Systems: Functions

Nervous and Endocrine Systems

The nervous system’s purpose is to generate responses that provide protection. It is based on the body’s ability to respond to stimuli. Stimuli that humans and animals respond to may be of two types:

  • Internal: Not visible (e.g., changes in temperature).
  • External: Can be observed (e.g., responses to light).

The endocrine system complements the nervous system. It works via hormones produced by endocrine glands. These hormones travel through the blood to an organ or tissue

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