Biology human systems revision

Female Reproductive System

Produces ova (eggs) and supports the development of offspring throughout pregnancy.

Ovary

Primary female reproductive organ containing thousands of undeveloped ova.

Fallopian Tube

The canal through which the released ova travels to reach the uterus; typically the site of fertilization.

Uterus

Muscular organ where a fertilized egg implants and develops into a fetus.

Endometrium

Specialized inner lining of the uterus that nourishes a potential embryo or sheds during menstruation.

Cervix

Narrow neck connecting the bottom of the uterus to the top of the vagina.

Vagina

Elastic, muscular tube connecting the cervix to the outside of the female body.

Menstrual Cycle

A repeating series of biological changes in the female body preparing the reproductive system for pregnancy.

Average Menstrual Cycle Length

Typically around 28 days.

Ovulation

Release of a mature ova from the ovary into the fallopian tube, occurring around day 14 of the menstrual cycle.

Fertilization

Process occurring in the fallopian tube where a sperm cell meets and fuses with a released ova.

Zygote

The single-celled fertilized egg that results from the fusion of sperm and egg.

Blastocyst

The multi-celled structure that develops from the zygote on its way to implantation in the uterus.

Implantation

The process of the blastocyst embedding into the thickened endometrium of the uterus.

Testes

The male reproductive organs that produce sperm cells and testosterone.

Scrotum

Pouch of skin containing the testes, regulating their temperature for sperm viability.

Prostate Gland

A gland that secretes fluid into semen to nourish and protect sperm.

Epididymis

Coiled structure atop each testis where sperm cells mature and are stored.

Urethra

Tube that transports urine and semen out of the male body.

Semen

Fluid containing sperm and secretions from seminal vesicles and prostate gland.

Stages of Labour

The phases of childbirth: Stage 1 (Latent and Active Phase), Stage 2 (Delivery of the Baby), and Stage 3 (Delivery of the Placenta).

Placenta

Temporary organ formed during pregnancy that facilitates nutrient transfer from mother to fetus.

Testosterone

Primary male sex hormone responsible for male reproductive development and secondary sexual characteristics.

Circulatory System

A group of organs that work together to transport gases, nutrients, waste products, and heat throughout the body.

Heart

A pair of pumps composed of specialized cardiac muscle tissue that continuously contracts and relaxes.

Blood Vessels

A network of tubes that facilitate the physical movement and flow of blood to every part of the body.

Blood

A liquid organ that carries oxygen, water, and essential nutrients to cells while collecting carbon dioxide and waste products.

Atria

The two top chambers of the heart where blood enters.

Ventricles

The two bottom chambers of the heart that forcefully pump blood out of the heart.

Septum

A thick wall of tissue that separates the left side of the heart from the right side.

Valves

Four principal structures in the heart (tricuspid, pulmonary, mitral, and aortic) that ensure unidirectional blood flow.

Pulmonary Artery

Transports deoxygenated blood away from the heart to the lungs.

Pulmonary Vein

Returns oxygenated blood from the lungs back to the heart.

Aorta

The primary and largest artery that pumps oxygenated blood out to the entire body.

Vena Cava

Returns deoxygenated blood from the body tissues back to the heart, divided into superior and inferior parts.

Pulmonary Circulation

The pathway where deoxygenated blood is pumped from the right side of the heart to the lungs.

Systemic Circulation

The path of oxygenated blood from the left side of the heart to body tissues.

Arteries

Blood vessels that transport blood away from the heart under high pressure, characterized by thick elastic walls.

Veins

Blood vessels that return blood to the heart under lower pressure and contain one-way valves to prevent backward flow.

Capillaries

The smallest blood vessels whose thin walls allow for the exchange of nutrients, oxygen, and waste between blood and tissues.

Plasma

The clear liquid component of blood, constituting 55% of total blood volume, acting as a solvent for nutrients and waste.

Red Blood Cells (Erythrocytes)

Cells that carry oxygen and make up 45% of blood volume, containing hemoglobin.

White Blood Cells (Leukocytes)

Cells that defend the body against pathogens, comprising less than 1% of blood volume.

Platelets (Thrombocytes)

Cell fragments that help in blood clotting, preventing excessive bleeding.

Epiglottis

A flap that folds over the trachea during swallowing to prevent food from entering the lungs.

Diaphragm

A muscle that alters thoracic volume to aid in breathing by contracting and relaxing.

Fertilization

The biological process where a male sperm cell and female egg cell fuse to form a new organism.

Mammals

Warm-blooded vertebrates characterized by hair or fur, internal fertilization, and live birth.

Birds

Feathered vertebrates that lay hard-shelled eggs and utilize internal fertilization.

Reptiles

Cold-blooded vertebrates that lay soft, leathery eggs and typically utilize internal fertilization.

Amphibians

Vertebrates that undergo external fertilization, laying eggs in water.

Pollination

The transfer of pollen from the anther to the stigma, necessary for fertilization.

Pollinators

Animals that transfer pollen between flowers, often rewarded with nectar.

Petals

Colored structures of a flower that attract pollinators.

Sepals

Leaf-like structures that protect the floral bud before opening.

Stamen

The male reproductive organ of a flower, consisting of the anther and filament.

Carpel

The female reproductive organ of a flower, including the stigma, style, and ovary.

Vas Deferens

Tube sperm travels through