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Female Reproductive System: A Comprehensive Guide

Classified in Biology

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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,
... Continue reading "Female Reproductive System: A Comprehensive Guide" »

reproduction

Classified in Biology

Written at on English with a size of 1.41 KB.

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

Classified in Biology

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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,

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Invertebrate Reproduction: A Comprehensive Look

Classified in Biology

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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

Classified in Biology

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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" »

Reverse Transcriptase and Gene Therapy in Molecular Biology

Classified in 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

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Reproductive System and STDs: A Comprehensive Overview

Classified in Biology

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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" »

The Process of Digestion and the Urinary System: Functions and Kidney Failure

Classified in Biology

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Process of Digestion

Mouth: Enzyme amylase breaks the chemical bonds.

Esophagus: Epiglottis prevents food from entering the lungs. Peristalsis helps food pass through smooth muscles.

Stomach: Chemical digestion (pepsin breaks down proteins with acid). Mucus protects the stomach. Mechanical digestion produces chyme. Cardiac sphincter closes the stomach.

Small Intestine: Chyme enters the small intestine. Bile is released to aid in fat digestion. Enzymes from the pancreas and duodenum complete digestion. Nutrients are absorbed by the villi. Undigestible substances go to the large intestine for elimination.

Functions of the Pancreas:

  • Hormones to regulate blood sugar levels.
  • Produces enzymes to break down carbohydrates, lipids, and nucleic acids.
  • Produces
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Understanding Human Reproduction and Infertility

Classified in Biology

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Fertilization

Fertilization occurs when a sperm and an ovum unite, forming a zygote. This process requires both ovulation and sexual intercourse. It's only possible during a 24-48 hour window after ovulation, although sperm can survive up to 5 days inside the female reproductive tract. The sperm penetrates the ovum's covering, and a fertilizing membrane forms, preventing other sperm from entering. The nuclei of the sperm and ovum join. After fertilization, the zygote travels to the uterus. The corpus luteum continues to release progesterone, maintaining the thick endometrium walls and preventing menstruation. During its journey, the zygote divides, becoming a ball of cells called a morula (around day 4) and then a blastocyst (around day 5).... Continue reading "Understanding Human Reproduction and Infertility" »

Human performance

Classified in Biology

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Describe the location and Functions of the lateral occipital cortex (LOC), the fusiform face area (FFA) And the estrastriate body area (EAB).

The Lateral occipital complex (LOC) is a large region of the ventral stream of the Visual association cortex, and appears to respond to a wide variety of objects And shapes. // The fusiform face area (FFA) is located in the ventral stream, On the anterior fusiform gyrus. It recognizes facial features, but also the Activity of this region can be affected by previously learned information. // The Extraestriate body area (EBA) is located in the ventral stream posterior to the FFA and partly overlaps it. This region is specifically activated by Photographs, silhouettes, or stick drawings of human bodies or

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