The Internal Environment and Nutrition

All cells need to live in an internal environment that provides them with all the food and nutrients they need and allows cells to release waste substances. It is formed of interstitial plasma, and the plasma has to be continually renewed thanks to the blood, which transports nutrients and removes waste products. The circulatory system connects the other three systems involved in nutrition.

Blood Composition

• Blood Plasma (55%): Made up of water with minerals (90%), nutrients (glucose, amino acids, vitamins, etc.), waste products (urea, uric acid, CO2), proteins, and dissolved hormones.
• Blood Cells (45%): Includes erythrocytes (98-99%), leukocytes (granulocytes and agranulocytes), and platelets (1-2%).

Blood

Female Reproductive System

Key Components and Functions

Uterus

The myometrium, the middle layer of the uterine wall, is responsible for the contractions during childbirth.

Vagina

The vagina is an elastic tube that facilitates penetration during sexual intercourse.

Vulva

The vulva, the external female genitalia, consists of the labia majora, labia minora, and the clitoris, which is responsible for sexual pleasure.

Bartholin's Glands

These glands produce lubricant to facilitate sexual intercourse.

The Ovarian Cycle

Each ovarian cycle lasts approximately 28 days and consists of three phases:

1. Follicular Phase (14 days): An egg cell matures.
2. Ovulation: The mature egg is released from the ovary into the fallopian tube.
3. Luteal Phase (14 days): The corpus luteum,

The Locomotor System

The locomotor system is made up of the skeletal system and the muscular system.

The Skeletal System

The skeletal system is formed by bones and joints.

Purpose of the Skeletal System

• To serve as an internal framework for our bodies.
• To protect organs and internal tissues.
• To provide anchorage support for muscles.
• To manufacture blood cells.
• To serve as a reserve store of calcium and phosphorus.

Bones

Bones are organs composed of compact bone tissue on the outside and spongy bone tissue at the core. To avoid friction, the ends of our bones are covered with cartilage. The holes in the spongy bone tissue are filled with bone marrow. There are two types: red bone marrow, in which blood cells are produced, and yellow bone marrow, which... Continue reading "Understanding the Human Locomotor System" »

Neurological and Mental Health Disorders

• Alzheimer's Disease

  Destruction of neurons in the cerebral cortex, leading to symptoms such as memory loss, disorientation, and behavioral changes.

• Parkinson's Disease

  Characterized by involuntary trembling (especially in the hands) and loss of muscle strength.

• Multiple Sclerosis (MS)

  An immune system-related disorder where the myelin sheaths and neurons destroy each other, affecting the entire body.

• Amyotrophic Lateral Sclerosis (ALS)

  A neuromuscular disorder involving the loss of function and death of motor neurons, resulting in slow paralysis and eventual death.

• Schizophrenia

  A lack of coordination between thoughts, feelings, and actions, often resulting in the person living an isolated life.

• Neurosis

  Chronic

Identical twins: once fertilization happens zygot break in two Different cells and each one give a different person but as they have the same Genes they are identical.

Contraceptivemethods (is not going to be asked at exam)

Assisted reproduction

Artificial insemination: sperm is placed inside the uterus During ovulation period using a syringe

IVF In vitro fertilization they get egg cell and join them With sperm using a microscope, once fertilization and the zygote develop to Blastocyst it is implanted in the uterus.

Ecosystem

Abiotic (physical, chemical), Biotic (population mateixa, community totes)

get food by: feeding, trophic relation shipsTrophic levels: 1) Producers 2)Consumers 3)Decomposers (bacteria, fungi)Organic materials: from living beings.
Photosynthesis: plants absorve inorganic matter(CO2, H2O, Sunlight) and produce organic matter (glucose, oxygen). Is produced in the clorophila (on cloroplasts). Nutritions: (1) autotrophs (photo and chemo), (2,3) heterotrophs (no photo)In a population relation of feeding: Cannibalism *mothers eat offspringChemoautotrophs: on acuatic volcanos 5km under sea,there were bacteria that do the chemosynthesi (because sunlight doesn't arrive): convert inorganic matter into organic through chemical substances (methane,

Invertebrate Reproduction

Porifera (Sponges)

They perform both types of reproduction:

• Asexual Reproduction: A small piece of sponge breaks off, anchors to a surface, and regenerates into a complete organism.
• Sexual Reproduction: This requires two individuals of opposite sex. They form sexual cells (sperm and ovum) that join together and produce a larva. The larva then anchors to a surface and grows, forming a new individual.

Polyps

They reproduce both asexually and sexually:

• Asexual Reproduction: A small bud forms and remains attached as it grows. It separates from the parent organism only when mature and then anchors to a surface.
• Sexual Reproduction: This requires two individuals of opposite sex. They form sexual cells (sperm and ovum) that join

Head and Neck Anatomy

Meninges and Sinuses

Falx Cerebri

Located between the two cerebral hemispheres.

Falx Cerebelli

Located between the two cerebellar hemispheres.

Tentorium Cerebelli

Located between the cerebrum and cerebellum.

Single Sinuses

• Superior sagittal sinus
• Inferior sagittal sinus
• Straight sinus
• Occipital sinus
• Basilar sinus

Paired Sinuses

• Sphenoparietal sinus
• Cavernous sinus
• Superior petrosal sinus
• Inferior petrosal sinus
• Transverse sinus
• Sigmoid sinus

Cavernous Sinus

Site: Sphenoid bone, extending to the superior orbital fissure.

Size: 2cm long, 1cm wide.

Structures within the Lumen:

• Internal carotid artery
• Abducent nerve

Structures in the Lateral Wall:

• Oculomotor nerve
• Trochlear nerve
• Ophthalmic nerve
• Maxillary nerve

Tributaries:

• Ophthalmic vein
• Superficial middle

Digestive System Fundamentals

1. What does the mucous membrane do? It absorbs nutrients and protects the surface of the duct.
2. What is the function of the large intestine? It absorbs water and electrolytes.
3. What types of digestion occur in the mouth? There are two types: physical and chemical.
4. What organs are located on the right side of the abdomen? Primarily the liver and the gallbladder.
5. What is the epiglottis? A flap of cartilage that prevents food from entering the trachea.
6. What are the two valves of the stomach? The cardiac (esophageal) sphincter and the pyloric sphincter.
7. What is the function of the salivary glands? They produce saliva to begin chemical digestion.
8. What are the two types of carbohydrates? Simple and complex carbohydrates.
9. What are

Reverse Transcriptase

Production of DNA from RNA

Reverse transcriptase is an enzyme isolated from retroviruses that catalyzes the production of DNA from an RNA template.

Use in Molecular Biology

• Reverse transcriptase is used in recombinant DNA technology to produce genes for gene transfer.
• It catalyzes the production of complementary DNA (cDNA) from an mRNA template.
• cDNA does not contain introns because mRNA undergoes splicing before cDNA production.
• Bacteria lack the machinery for intron removal, so genes inserted into them need introns removed to produce functional proteins.
• Examples of reverse transcriptase use include:
  • Mass production of human insulin by E. coli.
  • Generation of cDNA libraries for DNA microarrays (DNA fingerprinting).

Gene Therapy

Somatic