science B3 Flashcards
what are enzymes? (or what do they do)
chemically digests large starch molecules into smaller sugar molecules. (found in saliva)… Enzymes are biological molecules (typically proteins) that significantly speed up the rate of virtually all of the chemical reactions that take place within cells. They are vital for life and serve a wide range of important functions in the body, such as aiding in digestion and metabolism
Chemical digestion
the breakdown of large particles into
smaller particles by substances called enzymes
Mechanical digestion
physical breakdown of food into very small pieces
digestive system
is in charge of breaking down the food you eat into parts small enough to be used by your cells. OR Digestion is the breakdown of food into small molecules, which are then absorbed into the body
peristalsis
a wave of motion caused by contraction and relaxation of muscle tissue. (Such as in the esophagus.)
epiglottis
As you swallow, a flap of skin called the epiglottis moves across your windpipe, and food is funneled into the esophagus.
esophagus
the stretchy tube that food travels down from the back of the throat to the stomach.
stomach
stores food that arrives from the esophagus. breaks down the food with acid and physical churning. empties into small intestine.
Gastric Juice
is made of mucus, hydrochloric acid and enzymes
to chemically break down food.
villi
small, finger‐like projections that increase
the surface area (in the small intestine) to aid in absorbing nutrients. (nutrients are absorbed into the bloodstream by special structures called villi)
microvilli
The cells of the epithelial tissue have modified cell membranes that form more finger‐like projections called microvilli. Microvilli further increase the surface area of the
small intestine to help absorb nutrients. (located on the outside of the villi)
small intestine
breaks down food into even smaller parts using enzymes from the pancreas and bile from the liver. most nutrients are absorbed here
large intestine
removes waste from the small intestine. It absorbs any remaining water. transmits waste for eliminations. removes solid waste in ES
excretion
the job of waste removal in ES
excretory system
different organ systems interact to get rid of wastes.
urea
the body’s breakdown of proteins and ammonia. It can also be chemically composed into a liquid or a solid using ammonia and carbon dioxide.
liver in ES
takes the highly toxic ammonia produced by the body’s
cells out of the bloodstream and converts it into a less
harmful substance called urea
kidney in ES
are the main organs of excretion
they act as filters to the blood, straining out the unwanted
urea, water, and other salts, and they produce urine.
the skin in es
the skin functions by eliminating excess water and salt through sweat glands
sweat glands
in addition to producing sweat to keep you cool, these glands remove excess salt from your blood.
formation of urine
- Blood enters the kidney by the renal artery. 2. The artery branches into smaller and smaller vessels.
- These capillaries enter filtering units called nephrons.
- These microscopic nephron units remove wastes from the blood and produce urine.
- The “clean” filtered blood returns to the body through the renal vein. 6. The urine flows out a separate vessel and into the ureter to leave the body.
nephrons
nephron units remove wastes and produce urine.
Ureters
Ureters are long tubes that connect the kidneys to the
bladder.
urethra
When bladder is full, the bladder
muscles contract and push the
urine out through the urethra.
autonomic nervous system
controls muscles and has -Sympathetic (Fight or Flight)
- Parasympathetic (Rest & Digest)
axon
An axon, or nerve fiber, is a long slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron’s cell body or soma. Axons are in effect the primary transmission lines of the nervous system, and as bundles they help make up nerves.
the brain
is the control center. divided into three parts: the cerebrum, cerebellum and the medulla. the cerebrum controls voluntary movements and the senses and is divided into two halves. The cerebellum provides feedback on body positioning based on sensory information. The medulla controls the spinal cord and controls involuntary movements.
central nervous system
includes the brain and the spinal cord. together, they regulate activities of body
dendrites
Dendrites are the segments of the neuron that receive stimulation in order for the cell to become active. They conduct electrical messages to the neuron cell body for the cell to function.
Motor neurons
Motor neurons carry information from the central nervous system to the muscles or organs.
nervous system
The nervous system is a complex collection of nerves and specialized cells known as neurons that transmit signals between different parts of the body. It is essentially the body’s electrical wiring
nervous tissue
• Nervous tissue is made entirely of specialized cells called
neurons.
neurons/ nerves
nerves are made up of specialized cells called neurons that carry messages from one part of the body to the other using electrical signals. neurons send and receive
peripheral nervous system
includes all of the nerves outside the cns. pns connects the cns to the muscles, organs, and skin to help coordinate movements and behaviors. the PNS includes the automatic nervous system and somatic. Somatic controls voluntary action and reflexes.
sensory neurons
carry information from the body to the central nervous
system
somatic nervous system
Somatic controls voluntary action and reflexes.
senses
The sense of touch is found in all areas of your skin, making it the largest sense organ.
function of RS
1 supplying your blood with oxygen and #2 removing the carbon dioxide from your blood
diaphragm
Breathing occurs because of your rib and diaphragm muscles. Inhale- these muscles contract, pulling your ribs up, and your diaphragm down. pulls air into your lungs. Exhale- these muscles relax: your ribs go down and your diaphragm goes up. This decreases the size of your chest and lungs,
lungs in RS
the primary organ of the RS. They take in oxygen and expel carbon dioxide. they are inflated and deflated by the action of the diaphragm
alveoli
are made up of specialized epithelial tissue, only one cell layer thick. allows for diffusion of co2 and o2. tiny sacs in the lungs that allow co2 and o2 to move between the lungs and bloodstream
bronchi,bronchus, bronchiholes
bronchi are lined with tough connective tissue to keep walls from collapsing. bronchi are the main passageways into the lungs. they become smaller and are called bronchiholes inside the lungs. They then evolve into tiny air sacs called alveoli
function of CS
1 TRANSPORT the nutrients to each
cell in your body
#2 TRANSPORT oxygen to your cells
and carry waste products away.
veins
are blood vessels that transport blood from various regions of the body back to the heart. Veins are thinner and have valves that stop blood from flowing backwards
right and left side of the heart
The right side of the heart pumps blood to your lungs (where it receives fresh oxygen and gives off carbon dioxide).
The left side of your heart receives this oxygen-rich blood from your lungs and pumps it to all the other parts of your body.
the heart
is a muscular pump that circulates blood throughout the body. the heart pumps the blood that not only carries oxygen and glucose but also carries waste such as co2. has 4 chambers, 2 atria and 2 ventricles
four chambers in the heart
Right atrium: receives blood low in oxygen from the body
and pumps it into the right ventricle.
• Right ventricle: receives the blood and pumps into the lungs.
• Left atrium: picks up the o2 rich blood from the lungs and pumps it
to the left ventricle.
• Left ventricle: pumps the blood throughout the body.
arteries
are blood vessels that transport oxygen rich blood away from the heart to many places in the body. Aorta is largest artery in the body. have a thick muscular layer in the middle that expands and contacts to help move blood
lungs in CS
It carries oxygen from the air we breathe to cells throughout the body. The pumping of the heart drives this blood flow through the arteries, capillaries, and veins. One set of blood vessels circulates blood through the lungs for gas exchange. The other vessels fuel the rest of the body.
capillaries
Capillaries are very thin blood vessels. They bring nutrients and oxygen to tissues and remove waste products. Capillaries have two adaptations for
exchanging gases and nutrients:
1) They are made of specialized epithelial tissue that is only one cell layer thick
2) They are very narrow so that the blood cells must pass through in single file
blood ( plasma, platelets, red and white blood cells)
- red blood cells- carry oxygen, mature ones have no nuclei
- white blood cells- fight infections
- platelets- clotting cells that stop bleeding
- plasma- liquid part
plasma makes 55% of your body while others make 45%
spinal cord
helps carry messages in between the brain and body.
