Photosynthesis and Chemosynthesis Processes

– Phase Cyclic Light:

Intervenes only in PSI, resulting in the synthesis of ATP. Because PSII is not involved, nor is photolysis, consequently, there is no oxygen production or clear reduction of NADP+. The aim of the cyclic phase is to solve the ATP deficit found in the acyclic phase to carry out the subsequent dark phase. The cyclic phase occurs when illuminated with light of a wavelength greater than 680nm, called far-red.

– Phase Dark Biosynthetic

It consists of the addition of CO2 to a sugar called

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Cell Structure, Metabolism, and Division: Essential Concepts

Cell: The Building Block of Life

The cell is the fundamental functional and morphological unit of all living things.

Eukaryotic Cell

All eukaryotic cells, including plant and animal cells, have membrane-enclosed compartments (organelles) within their cytoplasm where specific chemical reactions occur. Their hereditary material is contained within a nucleus.

Cell Morphology

Cells vary in shape, often spherical, depending on their function or lack thereof.

Plasma Membrane

The plasma membrane is a single,

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Human Body Systems: Nervous, Excretory, Digestive, Respiratory

Nervous System: Cells

The nervous system is composed of neurons and glial cells. Neurons transmit nerve impulses and do not regenerate. A neuron consists of a cell body, dendrites, and an axon. The space between neurons is called a synapse, where neurotransmitters facilitate communication. Nerve impulses travel from the cell body to the axon.

Types of Neurons:

  • Sensory (afferent) neurons: Carry information from receptors to the central nervous system.
  • Interneurons: Exist within the central nervous system
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Chromosome Alterations and Genetic Engineering Techniques

Chromosomal Alterations

Structural Alterations

These affect the structure of chromosomes, impacting gene location. They are usually caused by errors in mitosis and meiosis, mainly affecting homologous chromosome pairing during prophase I. There are four types:

  • Deficiencies or Deletions: Loss of a chromosome segment, affecting multiple genes. Example: Cri du chat syndrome.
  • Duplications: Repetition of a chromosome segment, often in heterozygous series. Cytologically recognized during mating as a duplicated
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Cellular Respiration and Fermentation Processes

Cellular Respiration

Cellular respiration is the process where glucose is completely oxidized to CO2 and H2O with O2 intervention. This catabolic pathway occurs in the mitochondria of eukaryotes or in the cytoplasm and plasma membrane of prokaryotes.

The pyruvate obtained in glycolysis is broken down in three stages:

1. Oxidative Decarboxylation of Pyruvate

Pyruvate from glycolysis enters the mitochondrial matrix and undergoes decarboxylation, releasing a CO2 molecule, while NAD+ is reduced to NADH.

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Understanding Species Evolution

What is a Species?

A species is defined as a group of organisms capable of interbreeding and producing fertile offspring.

How Does Evolution Occur?

Natural Selection

Charles Darwin proposed natural selection, or “survival of the fittest,” as the driving force behind evolution. For example, in a lion pride, the strongest cubs are more likely to survive and reproduce, passing on their advantageous traits. Over generations, these accumulated changes can lead to the emergence of a new species.

Jean-Baptiste

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