Lipids, Carbohydrates, Amino Acids & Peptides in Biochemistry
Lipids
Esfingoglucolipids
In sphingolipids, the polar group that binds to the ceramide is a carbohydrate that can be a monosaccharide or a branched oligosaccharide. The sphingolipids are arranged in the outer zone of the plasma membrane with glycoproteins forming the glycocalyx. Depending on the carbohydrate portion, they are classified into:
- Cerebrosides: Consist of a ceramide and a monosaccharide. They are abundant in the membranes of nerve cells in the brain and peripheral nervous system.
- Gangliosides:
Plasma Membrane and Cytoplasm: Structure and Function
Plasma Membrane
The plasma membrane, also known as the cell membrane, is the first layer that surrounds the cell, separating its internal components from the external environment. It is a dynamic structure that allows for changes in cell shape and movement.
Structure
The plasma membrane has a consistent structure across all cells and is closely associated with cytoplasmic organelles. According to the fluid mosaic model proposed by Nicholson, the membrane is primarily composed of a double layer of lipids.
Read MoreThe fascinating process of photosynthesis
Hypothesis: Autotrophs
Various circumstances led to the appearance and development of autotrophs, including:
A. – Initiation of Photosynthesis
As primitive organisms multiplied, the substances available to them in the seas decreased, leading to increased competition. Organic synthesis likely continued to occur in the atmosphere, but too slowly to restore equilibrium in the consumption of energy reserves in the seas.
Under these conditions, any variation that allowed an organism to manufacture its own
Read MoreGenetics and Heredity: Understanding Inheritance Patterns
Genetics and Heredity
Introduction to Genetics
Genetics is the science that studies the inheritance of characters, their evolution, transmission, and expression.
Basic Concepts in Genetics
- Haploid: A cell or body containing only one gene for each character.
- Diploid: A cell or body containing two genes for each character.
- Genes: Specific DNA segments that control structures and cellular functions. These are Mendel’s hereditary factors.
- Chromosomes: Structures in the nucleus of eukaryotic cells, formed by
DNA Replication, Transcription, and Genetic Information Flow
DNA: The Blueprint of Life
Griffith’s Experiment
Griffith worked with two strains of bacteria: a rough strain (R) and a smooth strain (S). The R strain lacked a polysaccharide capsule and was harmless to mice. The S strain, possessing a polysaccharide capsule, caused fatal infections. When dead S strain bacteria were mixed with live R strain bacteria and injected into mice, the mice died. This suggested a transforming principle from the dead S strain bacteria had altered the live R strain.
Hershey-
Read MoreMeiosis and Apoptosis: Cellular Processes Explained
Meiosis
Each organism has a characteristic chromosome number. Gametes (cells specializing in sexual function) have half the chromosome number of somatic cells (which form the rest of the body). These are referred to as haploid (n) and diploid (2n), respectively. The diploid cell produced by the fusion of two gametes is called a zygote. The purpose of meiosis is to reduce chromosome number and establish restructuring in homologous chromosomes through the exchange of genetic material.