Core Concepts of Evolution and Genetics
Natural Selection and Adaptation
Natural selection is the process where organisms with traits that help them survive and reproduce in their environment pass those traits to their offspring. Over time, this leads to adaptation, where species become better suited to their environment.
Genetic Drift
Genetic drift occurs when random events change the frequency of genes in a small population. Unlike natural selection, it doesn’t depend on how advantageous the traits are. For example, if a natural disaster
Read MoreUnderstanding the Human Coordination Systems: Nervous & Endocrine
The Coordination System: An Overview
The coordination system enables us to detect environmental changes, analyze them, and respond accordingly. This is primarily achieved through two systems:
- The Nervous System: This system facilitates rapid but short-lived responses. It operates through nerve impulses transmitted along nerves.
- The Endocrine System: Composed of endocrine glands, this system produces slower but more enduring responses. It functions via chemical messengers called hormones.
Elements Involved
Read MoreUnderstanding Human Sensory Receptors and Brain Anatomy
Human Sensory Receptors
Photoreceptors: Light – eyes – sight
Mechanoreceptors: Pressure (movement) – skin and muscles – touch
Vibration (waves): Ears – hearing
Chemoreceptors: Dissolved chemical substances – tongue – taste
Volatile chemical substances: Nasal passage – smell
Thermoreceptors: Changes in temperature – skin – touch
Brain Anatomy and Function
Cerebrum | Skull Meninges Cerebrospinal fluid | – Largest part of the brain – Made of white matter (inside) and grey matter (outside) – Divided into hemispheres | Responsible |
Upper and Lower Limb Anatomy: Muscles, Arteries, and Nerves
Upper Limb Anatomy
Superficial Posterior Muscles
- Trapezius
- Deltoids
- Biceps brachii
- Triceps brachii
- Brachioradialis
- Flexor carpi ulnaris
- Anconeus
- Extensor carpi ulnaris
- Extensor digitorum
Anterior Muscles
- Trapezius
- Deltoids
- Biceps brachii
- Triceps brachii
- Pectoralis major
- Brachialis
- Brachioradialis
- Pronator teres
- Flexor carpi radialis
Deeper Muscles (Back)
- Levator scapulae
- Rhomboid minor
- Rhomboid major
- Supraspinatus
- Infraspinatus
- Teres minor
- Teres major
- Latissimus dorsi
Anterior Ligaments
- Coracoacromial ligament
- Superior transverse
DNA Replication and Operons: Mechanisms in Prokaryotes and Eukaryotes
DNA Replication in Prokaryotes: Initiation and Elongation
Initiation Phase: In prokaryotes, DNA replication begins with the initiation phase.
Elongation Phase: This phase involves the synthesis of a new DNA strand. Several DNA polymerase enzymes are involved, primarily DNA polymerase I, II, and III. These enzymes have a dual function:
- Polymerase Activity (5′-3′): Nucleotides bind to the DNA, recognizing the template strand and selecting complementary deoxyribonucleotides. The energy for forming new
Protozoa, Algae, Monera, and Viruses: Characteristics & Types
Protozoa: Characteristics and Types
- Features:
- Unicellular organisms capable of performing all vital functions.
- Heterotrophic: They feed on bacteria, organic debris, and other organic matter.
- Live in aquatic environments, both freshwater and saltwater; most are free-living.
- Types:
- Flagellates: Move by flagella. Some are free-living, and others are parasites. Trypanosoma causes sleeping sickness.
- Ciliates: Move by cilia. Free-living and parasitic. The Paramecium has two nuclei and is slipper-shaped.
- Rhizopods: