Lecture 1 Flashcards
What is the hierarchy of organization?
Atoms to Molecules to Cells to Tissues to Organs to Organ Systems to Organisms
What is the nervous system?
the most important control system, fast-acting, responds to internal and external changes. Central nervous system and peripheral nervous system (spinal cord, nerves, brain, sensory receptor)
What is the musculoskeletal system?
made of bones and muscles, occupies most of body allows manipulation of environment, locomotion, facial expression, maintains posture, produces heat (muscle)
What is the endocrine system?
made of glands that secrete hormones that regulate growth, reproduction, and nutrient use. all over the body: pineal gland, pituitary gland, thyroid gland, adrenal gland, pancreas (regulate glucose metabolism), ovary, testis
What do hormones regulate?
growth, reproduction, and nutrient use
What is the cardiovascular system?
Made of heart and blood vessels. Heart pumps blood. Blood vessels transport blood. Blood carries oxygen for metabolism and carbon dioxide as waste. Also carries nutrients to body and excretes wastes
What is the lymphatic/immune system?
Picks up liquids leaked from blood vessels and takes it back to the heart so it can go back to circulation. Houses white blood cells (immune cells or lymphocytes) to de
What is the lymphatic/immune system?
Picks up liquids leaked from blood vessels and takes it back to the heart so it can go back to circulation. Houses white blood cells (immune cells or lymphocytes) to defend our cells when bacteria or other things come in. Mounts attack against foreign substances in the body Red bone marrow (lymphocytes formed here), thymus, lymphatic vessels, thoracic duct, spleen, lymph nodes
What is the respiratory system?
Keeps blood supplied with oxygen, removes carbon dioxide. Gas exchange occurs through walls of air sacs in the lungs. Lungs, trachea, larynx, bronchus, pharynx, nasal cavity
What is the digestive system?
Breaks down food into absorbable units, indigestible foodstuffs eliminated as feces. Many different organs involved: oral cavity, esophagus, liver, stomach, small intestine, large intestine, rectum, anus
What is the urinary/excretory system?
Eliminates nitrogenous wastes. Regulates water, electrolyte (different ion concentrations), and acid-base balance. Kidney, ureter, urinary bladder, urethra
What is the male reproductive system?
Produces offspring. Testes produce sperm and male sex hormones. Penis, testis, scrotum, ductus deferens, prostate gland
What is the female reproductive system?
Produces offspring. Ovaries produce eggs and female sex hormones. Mammary glands produce milk. Mammary glands, uterus, vagina, ovary, uterine tube
What may be the smallest organ in the human system?
Ovary
What produces milk?
Mammary glands
What are the different organ systems (10)?
Nervous, musculoskeletal, endocrine, cardiovascular, lymphatic/immune, respiratory, digestive, urinary/excretory, male reproductive, and female reproductive systems
What do organs consist of?
Multiple tissues
Label this diagram of a gut wall of the small intestine.
What are the four types of tissues?
Epithelial tissues, connective tissues, muscle tissues, and neural tissues
What are epithelial tissues?
Sheets of densely packed, tightly connected epithelial cells
Where are epithelial tissues located?
What are the 3 functions of epithelial tissues?
Create boundaries between inside/outside of the body and between body compartments
Transport and filter substances (e.g., ion)
Secrete substances (e.g., digestive juices, milk)
Label this diagram and identify what it is.
Label and identify.
Label and identify.
What are muscle tissues?
What are the most abundant tissues in the body?
Muscle tissues
What are the three types of muscle tissues?
Skeletal, cardiac, and smooth
What are skeletal muscles mostly attached to?
Bones
What are skeletal muscles responsible for?
Locomotion and other body movements (e.g., breathing, shivering)
What is this?
Skeletal muscle.
What are some characteristics of skeletal muscle?
Highly organized structure, nuclei are squeezed to the side to maintain this structure.
What does the cardiac muscle make and what is it responsible for?
Makes up the heart, responsible for generating the heartbeat and moving the blood in the blood vessels (blood flow).
What is this? Label and describe features.
Cardiac muscle. Still organized, not as much as skeletal muscle. Stripes: variety of structure. Cells form branches and integrate with each other. Mesh-like structure allows cells to couple with each other better. Heart beat –> cells can go together. Heart attack is when different cells want to beat at different times
What causes a heart attack?
When different cardiac muscle cells want to beat at different times.
What does the smooth muscle make up?
The walls of internal organs (e.g., gut, bladder, blood vessels)
What is smooth muscle involved in?
Movement and generation of forces in internal organs
What is this?
Smooth muscle tissue
What is the structure of smooth muscle?
Smooth looking–don’t see the obvious stripes/organization like in skeletal and cardiac muscles
What is the function of connective tissue?
Connect, support, binds, or separate other tissues or organs
What is the main feature of connective tissues?
There is an extracellular matrix where relatively few cells are embedded (i.e., not densely packed unlike other tissues). The matrix contains protein fibers.
What are the 2 types of protein fibers in connective tissues, and where specifically are they located?
Collagen and elastin in the extracellular matrix
What is collagen?
A protein fiber in the extracellular matrix of connective tissues. Strong and resistant to tearing and stretching.
What is elastin?
Protein fiber in extracellular matrix of connective tissues that can be stretched and recoils
What is the proportion of collagen and elastin?
Can change depending on where the connective tissue is.
What are the 4 types of connective tissue?
Cartilage, bone, adipose, blood
What is the function of cartilage?
Cushions joints and provides structural support with flexibility (without it, one can get bone fractures)
What is another name for cartilage cells?
Chondrocytes
What is the structure of cartilage?
Chondrocytes (cartilage cells) not as tightly packed and surrounded by a matrix outside of the cells like big space-like structures
What is this? Label.
Cartilage
What is the function of bone?
Provides support
What is bone hardened by?
By calcium phosphate desposition in the matrix
What is this? Label
Bone.
Blood vessel is growing the cell. Little dots are different types of cells. Extracellular matrix is not obvious because many are calciumfied–all built with extracellular matrix material so you can’t see it clearly but there are many extracellular matrix surrounding the cell.
What is this? Label
Blood
What does blood consist of?
Cells floating in a very liquid extracellular matrix
What is the extracellular matrix of blood?
Blood plasma
What is the function of adipose?
Store energy (stores nutrients in droplets inside so it can provide when we need it), cushion organs, prevent heat loss (insulation layer and generate heat)
What are the two types of adipose?
White adipose and brown adipose
What is the function of white adipose?
Stores large droplets of lipids until we need it, secretes hormones that regulate our appetite, inflammatory molecules (produce inflammation signals that contribute to the immune system)
Which adipose is the most prevalent in our bodies?
White adipose
What was brown adipose thought to be before?
Only in babies, not in adults
Where is brown adipose in adults?
In collarbone area
What is the function of brown adipose?
Produces heat
What is brown adipose packed with?
Mitochondria (can burn energy and produce heat) and blood vessels (carry oxygen to provide mitochondria to heat)
Why does brown adipose look brown?
Because of lots of mitochondria
Why is there increased interest in brown adipose?
If we produce more brown adipose, we can help combat obesity. It produces heat that can burn fat.
What can mitochondria do?
Burn energy and produce heat
What do blood vessels do for mitochondria?
Carry oxygen to provide mitochondria to heat.
What do we need when we burn energy/have metabolism?
Blood vessels and mitochondria
What is this?
White adipose. Droplets of lipids in cell makes the cell big; can take up most of the cell
What is this?
Brown adipose. Looks more brown because of the mitochondria
What are neural tissues for?
Processing information
What are the two types of neural tissues?
Neurons and glial cells
What do neurons do?
Encode and conduct information as electrical signals
Release chemical signals (neurotransmitters) to target cells
light electrical signals –> go through cells –> become chemical signals for next target cell
What are neurotransmitters?
Chemical signals
What are dendrites?
The finger/tree-like structure of a neuron
What is an axon?
Extended line, a signal is transmitted through the axon
What are axon terminals?
Release neurotransmitters (chemical signals/information to communicate with the next cell)
What is this? Label.
Neuron
What do glial cells do?
Provide support functions for neurons. Can release neurotransmitters and generate chemical signals. Cannot carry electrical signals.
What is this? Label
Cell body of glial cells
What is this? What are in green and what are in red?
Green: neurons
Red: glial cells
Touching each other: glial cells are there for support
What do all cells need and how do they get these needs?
Nutrients, oxygen, and to eliminate waste products
Served by a stable internal environment of extracellular fluid: environment provides nutrients and oxygen, removes waste products, and is maintained by extracellular fluid
How much of the body is water, and how much of water is inside cells?
2/3, 2/3
What two fluids make up the internal environment for cells?
Intracellular fluid and extracellular fluid (ECF)
What are the two components to extracellular fluid?
Interstitial fluid and plasma
Interstitial fluid is ___% of extracellular fluid.
Plasma is ___% of extracellular fluid.
80%, 20%
Label.
What is homeostasis?
The maintenance of a narrow range of stable conditions in an internal environment to allow optimal body functions
Label.
Set point –> Sensor tells what current temperature is in the regulatory system –> Controlled systems turn on depending on our set point and what the difference is between set point and current.
What is the regulatory system?
System that obtains information through sensors, processes information, and integrates information, then issues commands to controlled systems.
Sets the desired point, obtains information, measures the environmental condition and compares to desired information, orders the other system around
What are the two systems to control homeostasis?
Regulatory and controlled systems
What is the controlled system?
System that contains effectors to effect changes in the internal environment; receives orders from the regulatory system to do something
What is the set point?
A reference point or desired condition
What does the sensor provide?
Feedback information, or what is happening in the system. It measure the condition.
What is the error signal?
Difference between the set point and the feedback information (Set point - Feedback information; set point is ___ than the error message)
What are the two types of feedback?
Negative and positive feedback
What happens with negative feedback?
Effectors counteract the error signal (e.g., thermostat)
What is the most common type of information?
Negative feedback
What happens in positive feedback?
Amplifies a response, increases the deviation from a set point (e.g., birth process)
What is feedforward information?
Changing the set point (e.g., exam time or a deer in the road when driving at the speed limit)
What is the range of temperature for humans?
36.5-37.5 degrees Celsius or 97.7 to 99.5 degrees Fahrenheit
At what temperature does heat stroke occur?
Greater than 40 degrees Celsius (104 degrees Fahrenheit)
At what temperature does hypothermia occur?
Less than 35 degrees Celsius or 95 degrees Fahrenheit
Why is temperature regulation important?
Because most cellular functions are limited to the range of 0-40° C in humans and animals and chemical reactions in the body are temperature-sensitive (higher temperature –> faster reaction; lower temperature –> slower reaction; rates are not all the same for different reactions; assembly line metaphor: can get very disorganized without regulation)
What happens below 0°C?
Ice crystals form and damage cell strictures (water freezes)
What happens above 40°C?
Proteins denature (structures change) and lose functions
What are the thermal classifications of animals?
Ectotherms, endotherms, heterotherms
What do ectotherms rely on?
The external temperature as their temperature. Can move around to regulate their temperature as needed. e.g., lizard
How do endotherms regulate their temperature?
Through internal mechanisms; maintain a stable internal temperature. e.g., monkey
What do heterotherms do?
Act as both ecto and endotherms sometimes. e.g., bear
What determines the temperature of an organism?
Energy balance
What is energy balance?
Heatin-Heatout
Determines temperature
Balance between heat absorbed and heat lost
What is Heatin?
Heat absorbed (e.g., sun) + metabolism (internal heat generated)
What is Heatout?
heat loss through surface areas (e.g., skin, lungs–breathing)
What needs to be equal for a stable temperature?
Heatin=Heatout
How does the body mainly generate heat?
Mainly through metabolism
–Blood vessels constrict, skeletal muscles contract, shivering, non-shivering thermogenesis
What is metabolism?
Chemical reactions to break down and synthesize molecules
In metabolism, what generally happens?
Some reactions absorb heat and others release heat, but generally, heat is generated.
What happens if we increase the metabolic rate?
More heat is generated
What happens if we decrease the metabolic rate?
Less heat is generated
What increases the metabolic rate?
Contracting muscles and brown fat
How does contracting muscle increase the metabolic rate?
Burns energy–> heat generated voluntarily or involuntarily
Ex. running is voluntary, shivering is involuntary
How does brown fat increase the metabolic rate?
Because it has tissue that has mitochondria and blood vessels, brown fat generates heat.
How does the body lose heat (2 ways)?
Mainly through surface areas: skin, lungs
Relaxing muscle to reduce metabolic rate (less heat generated)
Blood vessels dilate, skeletal muscles relax, panting, sweating
How does the body lose heat through surface areas?
It increases blood flow in blood vessels (blood vessels dilate or open up to go faster) to carry heat from internal organs to the surface areas (skin)
Evaporate water (sweat) –> Release of heat
Increase breathing frequency (panting) –> Release heat
What happens if you cool the hypothalamus?
Increases the metabolic rate and increases the body temperature
What happens if you warm the hypothalamus?
Decreases the metabolic rate and lowers the body temperature
What animal was used to discover that the hypothalamus controls the body temperature?
Ground squirrel–manipulating the hypothalamic temperature
What is the regulatory system of mammals?
the hypothalamus
In mammals, what is the set point generated by?
the hypothalamus
What is the negative feedback information in mammals?
The hypothalamus temperature, which is a mostly stable temperature and is hard to change
What is the sensor in mammals?
Skin temperature
What is the feedforward information in mammals?
A change in skin temperature shifts the set point of the hypothalamus
Label
What is the thermoregulatory response of an endotherm to a rise in temperature?
A. Increased metabolic heat production
B. Resetting of the thermostat to a higher setting
C. Dilation of blood vessels
D. Overall increase in body temperature
E. Initiation of shivering movements
C. Dilation of blood vessels
What is a fever and what is it caused by?
A rise in body temperature caused by pyrogens
What do pyrogens cause?
A rise in the hypothalamus set point
What are exogenous pyrogens?
External pyrogens–from foreign substances (comes into body –> immune response initiated)
e.g., bacteria or viruses
What are endogenous pyrogens?
Internal–produced by immune cells in response to infection
What does fever help?
Fight infections
What does a fever mimic?
The reaction to cold (shivering)
What type of feedback information does a fever send?
Negative feedback information (comparing Thypothalamus with the new set point)
What do fever-reducing drugs do?
Cause a decrease in the temperature set point in the hypothalamus
Label.
