human body

body cavities

cavities are fluid filled spaces that protect and support organs

four main body cavities

cranial (brain), vertebral (spinal cord), thoracic (heart and lungs), abdominal (digestive organs and kidneys).

ligaments

connect bones

tendons

muscle to bone

bone cells that form bones

osteocytes, osteoblasts, osteoclasts.

layers of bone

periosteum, compact bone, spongy bone, bone marrow

joints

locations where bones meet. can be fixed, movable, or semi movable.

central nervous system

spinal cord and brain; flow of information throughout body.

parts of brain

cerebellum, cerebrum, thalamus, medulla oblongata, hypotholamus

pns

nerves outside cns

parts of peripheral nervous system

somatic: controls voluntary movements. autonomic: involuntary movements.

vena cava

carries deoxygenated blood to the heart

aorta

carries oxygenated blood out of the heart

respiratory system

in the lungs, gas is exchanged between atmosphere and body. in the capillaries, gas is exchanged between cells.

esophagus

food to stomach

stomach

enzymes break down macromolecules

small intestine

nutrients needed for cellular respiration are absorbed.

large intestine

water and electrolytes absorbed

peristalsis

involuntary contraction of muscles in digestive system that move material throughout it

nephrons

water filters for kidneys in the blood

ADH hormone

controls how much water can be used for filtration by kidneys

fiber

aids in digestion, cant be used for energy

white blood cells

identify and destroy pathogens

antibodies

proteins produced by the body that lock on to antigens to mark them for destruction

1st line of defense (innate)

mucus, tears, skin. nonspecific defense, attempts to keep everything out.

2nd line of defense

inflammatory response. when a pathogen or injury is detected, cytokines and histamine are detected, causing swelling, redness, and elevated temperature. this allows other white blood cells to rush to the site and help.

phagocytes

engulf and ingest pathogens and remove dead, damaged tissue. examples are macrophages and monocytes.

3rd line of defense

adaptive immunity. antibodies released by b-cells identify pathogens by antigens. this stimulates t-cells to destroy pathogen or infected cell.

immunological memory

antibodies and t-cells are specific to a particular pathogen and form “memory” once exposed to their antigen, allowing for a faster response in the future.

lymphatic system

consists of lymph nodes, where pathogens are brought to be destroyed.

steroidal hormones

lipids that can cross cell membranes and interact directly with the DNA of the cell.

nonsteroidal hormones

proteins that can only attach to outside of a cell.

pineal gland

produces serotonin

thyroid

produces thyroxine and regulates metabolism

hypothalamus and pituitary gland

produces ADH, which controls water content of blood and FSH, which regulates sperm and egg production.

thymus gland

produces hormones that regulate t-cell and b-cell production for the immune system.

adrenal

produces adrenaline, which controls the bodys response to stress and can be used to counteract allergic reactions.

prenatal

before baby is born

blastocyst

approximately 100 undifferentiated cells. is formed when baby is still in fallopian tubes by mitosis.

embryo

a zygote which has implanted itself in uterus

notochord

part of embryo that becomes the central nervous system

fetus

when all body systems have begun development

infancy

rapid growth and nervous system development

childhood

fine motor skills, permanent teeth, bone growth

adolescence

puberty

adulthood

aging process begins to wear down some organ systems