Chromosomes, DNA, Genetic Engineering, and Biotechnology
Chromosomes
The number of chromosomes in a species remains constant. During the formation of sexual cells, the parents do not merely halve the number and rather carry 2 copies of each chromosome, only one is passed on.
Karyotype
Set of ordered chromosomes.
DNA
Whitish substance. Its chains form a double helix. Each chain is formed by phosphate groups, sugars, and nitrogenous bases: adenine, guanine, cytosine, and thymine.
Genes
A DNA fragment that contains the necessary information to synthesize a protein.
Read MoreDigestive Processes: From Small Intestine to Egestion
Small Intestine: Digestion and Absorption
The small intestine is involved in chemical digestion and absorption of nutrients. It is connected with valves to:
- The stomach through the pylorus.
- The large intestine through the ileocecal valve.
The small intestine has three parts:
- Duodenum: Primarily responsible for the digestion of proteins (using trypsin), carbohydrates (using pancreatic amylase), and fats (using lipase).
- Jejunum: Focuses on food absorption. The inner layer is full of folds called villi,
Micronutrients, Macronutrients, and Balanced Diet
Micronutrients and Their Effects on the Body
Micronutrients, primarily minerals and vitamins, are essential components of a healthy diet. They perform various crucial functions:
Minerals
- Calcium: Required for bone and teeth formation. Deficiency causes osteoporosis, rickets, and retarded growth.
- Iron: Necessary for the formation of hemoglobin. Deficiency leads to anemia.
- Phosphorus: Helps in making strong bones and teeth.
- Sodium: Supports the nervous system for better response. Deficiency causes cramps
Digestive, Respiratory, and Circulatory Systems
Digestive System Accessory Organs
These organs are located outside the digestive tract, although the digestive juices they secrete are passed into it. These juices contain a great variety of digestive enzymes (proteins that accelerate the breakdown of complex food into nutrients).
- The salivary glands: Three pairs of glands that secrete saliva into the mouth.
- The liver: The largest gland. It secretes bile, which is stored in the gallbladder. Bile helps us to digest lipids by acting as a detergent. The
Cellular Structures: Mitochondria, Chloroplasts & Nucleus
Mitochondria: Structure and Function
Outer membrane: Contains proteins that regulate the exchange of substances with the cytosol. Inner membrane: Consists of ridges and contains mitochondrial proteins. Matrix: The space inside the mitochondria; contains enzymes, DNA (as a double-stranded, closed circular molecule).
Mitochondria Function: Energy production.
Chloroplast: Structure and Function
Found in plant cells and photosynthetic eukaryotes.
- Outer membrane: Fluid mosaic.
- Inner membrane: No crests.
- Stroma:
Understanding Virology: Acronyms, Concepts, and Vaccines
Acronyms in Virology
- AIDS: Acquired immunodeficiency syndrome
- ART: Antiretroviral therapy
- ccc: Covalently closed circle
- CMV: Cytomegalovirus
- CPE: Cytopathic effects
- CTL: Cytotoxic T lymphocyte
- DLP: Double-layered particle
- EBV: Epstein-Barr virus
- ER: Endoplasmic reticulum
- ESCRT: Endosomal sorting complexes required for transport
- GFP: Green fluorescent protein
- HA: Hemagglutinin
- Hsp60: Heat shock protein 60
- ICAM-1: Intercellular adhesion molecule
- IFN: Interferon
- IHF: Integration host factor
- IRES: Internal ribosome