Lipids, Cell Biology, and Immunology Overview
Lipids
Properties and Classification
Lipids are organic molecules composed of carbon, hydrogen, and oxygen. Some complex lipids also contain nitrogen, phosphorus, or sulfur. Key properties include insolubility in water, solubility in organic solvents, and low density.
Lipids are classified into:
- Fatty acids
- Saponifiable lipids:
- Simple: Triacylglycerols and waxes
- Complex: Phosphoglycerides and sphingolipids
- Non-saponifiable lipids:
- Steroids
- Terpenes
- Icosanoids
Cholesterol
Cholesterol, a sterol, is present in
Read MoreHip, Knee, and Ankle Anatomy and Function
Hip Joint
Articulation
The hip joint is a ball-and-socket joint (enarthrosis/spheroidal).
Joint Surfaces
- Femur
- Hip Bone
Muscles
Flexors
- Iliopsoas
- Rectus Femoris (Quadriceps)
- Sartorius
- Tensor Fascia Lata
- Pectineus
Extensors
- Hamstrings (Biceps Femoris, Semitendinosus, Semimembranosus)
- Gluteus Maximus, Medius, and Minimus
Adductors
- Adductor Brevis, Longus, and Magnus
- Gracilis
Internal Rotators
- Gluteus Medius and Minimus
External Rotators
- Gluteus Maximus
- Iliopsoas
- Pectineus
- Adductors (Brevis, Longus, Magnus)
- Sartorius
- Tensor
Peroxisomes: Structure, Function, and Associated Diseases
Peroxisomes. In 1954, Rhodin found small organelles in the proximal tubule of mouse kidneys, which he called “microbodies.” In 1962, Novikoff discovered microperoxisomes. These self-replicating organelles, bound by a single membrane, are present in all eukaryotic cells. They contain enzymes and are involved in:
- Control of lipid homeostasis by beta-oxidation
- Conversion of cholesterol into bile salts (liver only)
- Plasmalogen biosynthesis
- Cellular respiration
- In plants, seed peroxisomes convert fatty acids
Cell Biology: Structure, Types, and Organization
1. The Cell: The Building Block of Life
Organic and inorganic compounds group together to form cells. All living things are composed of one or more living cells. The cell is the smallest unit capable of performing three vital functions: nutrition, interaction, and reproduction.
Human cells are eukaryotic, meaning their genetic material (DNA) is housed within a double-membraned nucleus. The cytoplasm is compartmentalized into numerous organelles, each performing specialized functions. While human
Read MoreIntroduction to Microbiology
Questions and Answers in Microbiology
1. The first observer of bacteria under the microscope was:
A) Robert Hoock
B) Robert Koch
C) Anton van Leeuwenhoek
D) Beijerinck
2. The scientist Sergei Winogradsky is connected with the development of:
A) Microbial ecology
B) Heterotrophic metabolism
C) Aerobic bacteria
D) All of the above
3. Which scientist(s) related to the field of microbiology influenced the area of agronomy?
I) Fleming II) Beijerinck III) Winogradsky
A) Only II)
B) Only III)
C) II) and III)
D) I), II)
Genetics, DNA, and the Human Genome: A Comprehensive Overview
1. Chromosomes
Genes reside within the cell nucleus, on structures called chromosomes. Every species has a characteristic number of chromosomes in each cell. Humans possess 46 chromosomes. This number remains constant due to the halving of chromosomes during sex cell formation. Human sperm and eggs each contain 23 chromosomes, which combine during fertilization to form a zygote with 23 pairs. Gametes (sex cells) are haploid (n=23), while somatic cells (body cells) are diploid (2n=46). Of the 46 chromosomes,
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