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Common Diseases and Disorders: Definitions and Symptoms

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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

... Continue reading "Common Diseases and Disorders: Definitions and Symptoms" »

reproduction

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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.

Understanding Ecosystems and Human Impact

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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,

... Continue reading "Understanding Ecosystems and Human Impact" »

Invertebrate Reproduction: A Comprehensive Look

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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
... Continue reading "Invertebrate Reproduction: A Comprehensive Look" »

Head and Neck Anatomy: Sinuses, Nerves, and Muscles

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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
... Continue reading "Head and Neck Anatomy: Sinuses, Nerves, and Muscles" »

Digestive System Anatomy and Physiology Q&A

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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
... Continue reading "Digestive System Anatomy and Physiology Q&A" »

Reverse Transcriptase and Gene Therapy in Molecular Biology

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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

... Continue reading "Reverse Transcriptase and Gene Therapy in Molecular Biology" »

Giardia duodenalis: Classification, Morphology, and History

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Introduction to Giardia duodenalis

  • Giardia duodenalis is also known as Giardia lamblia and Giardia intestinalis.
  • It is a flagellated unicellular eukaryotic microorganism that colonizes and reproduces in the small intestine.
  • It commonly causes a gastrointestinal condition known as Giardiasis.

Unrelated Content Block

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Classification of Giardia duodenalis

  • There are five species of Giardia, of which G. intestinalis infects humans and other mammals.
  • G. duodenalis can further be differentiated into seven genotypes (A to G), of which genotypes A and B usually infect humans.

History and Global Distribution of Giardiasis

  • It is one of the earliest protozoan parasites to have been
... Continue reading "Giardia duodenalis: Classification, Morphology, and History" »

Cell Biology Fundamentals and Laboratory Procedures

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Variables en la Investigación Científica

La variable independiente es la que se modifica intencionalmente (la cantidad de agua), la variable dependiente es la que se observa y mide como respuesta a la variable independiente (tiempo que tarda en crecer), y las variables de control se mantienen constantes (luz, temperatura) para garantizar que los resultados sean confiables y precisos.

Microscope Slide Preparation Steps

  1. Place a drop of water or mounting medium on a clean microscope slide.
  2. Add your specimen to the drop.
  3. Carefully lower a coverslip onto the specimen, avoiding air bubbles.
  4. Seal the edges and label the slide.
  5. Observe the specimen under a microscope.
  6. Clean up.

Common Bacterial Shapes and Classifications

Bacteria can have various shapes, including:... Continue reading "Cell Biology Fundamentals and Laboratory Procedures" »

Reproductive System and STDs: A Comprehensive Overview

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Activites

1.) Difference between primary and secondary sex characteristics:

The primary are the sexual organs which are born with and the secondary are the physical characteristics developed during puberty

2.) Reproduction:

Is the creation of new individuals

3.) Explain the journey of sperm to the ovum:

After been secreted by the penis through the urethra, the sperm go from the vagina to the uterus, Then, they divide in 2 groups and go to each fallopian tube. If there’s an ovum, one of these single sperm will fertilize it, and they will form a zygote, divides and becomes a morula and later a blastocyst. On the 7 days, the blastocyst implants in the endometrium

4.)

-Gametes

Sperm

Ova

-Gonads

Testes

Ovaries

Reproductive tract

Epididymis, urethra

Fallopian

... Continue reading "Reproductive System and STDs: A Comprehensive Overview" »