Marine Life and Ocean Ecosystems: A Comprehensive Study

Marine Life and Ocean Ecosystems

Benthic Organisms

Epifauna: Organisms living on the surface of the ocean floor, such as corals, mussels, sea stars, sea urchins, and sponges.

Epibenthos: Organisms that live in association with the seafloor but swim up into the water column, such as carpet sharks, shrimp, and rays.

Hard Bottoms: Animals adapted to live on the top of rocks.

Infauna: Organisms that live burrowed into the ocean floor, such as clams and polychaetes. They use tubes for food and oxygen supply.

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DNA, Genes, and Chromosomes: Understanding Heredity

Before the Nineteenth Century: Inheritance by Mixing

Sex cells combine hereditary material and mix as do colors. According to this theory:

  • White Animal + Black Animal = All descendants are mid-gray.

Mid-Nineteenth Century

Gregor Mendel (1821-1884)

  • Modern genetics.
  • Inherited characteristics are transmitted by individual factors that are dispatched each generation.
  • Not-ruined compote that was identified as hereditary material.

Mendel’s Experiments

Mendel’s experiments with peas involved smooth peas and wrinkled

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Acellular Bodies, Viruses, and Cellular Organelles

Acellular Bodies and Viruses

Acellular bodies are not living organisms.

Viruses

-Virus: Small molecules of DNA or RNA covered by a protein capsule (capsid). This capsule, composed of capsomeres, may have a neck, an outer shell, and various structures. Viruses are responsible for numerous parasitic infections and diseases. They are very small and can only live within other cells, using the host cell’s organelles to multiply.

Viral Life Cycle

Cycle of a virus:

  • Attachment: The virus binds to the surface
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Nervous and Endocrine Systems: Functions and Mechanisms

The Nervous System: Structure and Function

The nervous system comprises the central nervous system (CNS) and peripheral nerves. It is composed of cells called neurons that can carry rapid electrical impulses.

Nerve Impulse Conduction

Nerve impulses are conducted from receptors to the CNS by sensory neurons, within the CNS by relay neurons, and from the CNS to effectors by motor neurons.

Resting and Action Potentials

  • Resting potential: The electrical potential across the plasma membrane of a cell that
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DNA Structure and Genetic Information

DNA as a Carrier of Genetic Information

In the early twentieth century, it was accepted that genes were on chromosomes and that they were the carriers of genetic information. However, the evidence that genes are made of DNA (not protein) and its acceptance in the scientific community did not take place until 1950.

Chemical Composition of Nucleic Acids

There are two types of nucleic acids: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Both are long polymers of nucleotides. They consist of

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Water, Minerals, Carbohydrates, and Buffers: Properties and Biological Functions

Properties of Water

  • The water temperature in a liquid environment: freezing point (FP) is 0°C, boiling point (BP) is 100°C.
  • Water has strong cohesion between its molecules (capillarity).
  • High surface tension, causing surface tension.
  • High heat of vaporization: much energy is needed to change liquid water to a gaseous state due to the large number of hydrogen bonds.
  • It’s a good solvent for ionic and polar substances (due to its polarity).
  • Has a high specific heat, so it can buffer heat.

Heat of Vaporization

The

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