Ch. 40 Intro to Animals Flashcards
big ideas: tissue types, homeostasis, + and - feedback, bioenergetics & metabolic rates
what is the relationship between surface area and volume?
surface area increases more slowly than volume
how do simple animals [ex, unicellular] access nutrients and remove wastes?
through diffusion and active transport across membranes
how do cells in large animals [humans] access nutrients and remove wastes?
through organ systems & interstitial fluid
what is interstitial fluid?
fluid [composed of water & solutes] located between cells
what is the function of interstitial fluid?
to allow for fast diffusion of gases, nutrients, and wastes between circulatory systems and cells
what is the function of connective tissue?
to form the “framework” of the body & bind tissues together
what is the hierarchy of body plans from smallest to largest?
cells -> tissues -> organs -> organ systems
what is the function of epithelium tissue?
to line the inner & outer surfaces of the body
what is the function of nervous tissue?
communication, coordination of body activities
what is the function of muscular tissue?
to move the body and its contents through excitation/contraction
what are the two forms of epithelial tissue?
- thin, single cell layers - for diffusion [lungs]
- multilayered cells - for protection [inside of mouth]
what is the definition of an organ?
an organ is different types of tissues arranged in a specific fashion
what is an organ system?
different organs working together with a common function
what is the function of microvilli?
to increase surface area for absorption [in areas where body needs it - intestine/kidney]
what is a lumen?
the inside space of an organ structure, such as the inside of a blood vessel or intestines
what is the function of cilia?
to move mucus in various parts of the body [ex, respiratory tract]
what are the three SIMPLE epithelial cell types?
- squamous
- cuboidal
- columnar
what are the three classes of epithelium?
- simple = one cell layer thick
- pseudostratified columnar = one layer of columnar cells that looks like multiple layers
- stratified = multiple cell layers
what is the structure of connective tissue?
-composed primarily of extracellular matrix with a small number of cells distributed within
what is extracellular matrix?
a complex of proteins and “fluid” organized in a haphazard way
what is the most common fiber in connective tissue?
collagen
what are the 6 types of connective tissue?
loose CT
adipose CT
dense CT
cartilage
bone
blood
what is the function of loose connective tissue?
to serve as “glue” to bind different tissues together
what is the function of adipose connective tissue?
to cushion, insulate, and store energy [adipose = fat = energy]
what is the function of dense connective tissue?
bind bone to bone = ligaments
bind muscle to bone = tendons
support for skin & other tissues
what is the function of cartilage?
to provide flexible support for key parts of the body [joints, ribcage]
what is the function of bone?
to support the body’s weight & produce red blood cells
what is the function of blood?
to transport gases, nutrients, hormones, and more throughout the body
what are the three types of muscular tissue?
skeletal, cardiac, and smooth
what is the function of skeletal muscle? is it voluntary or involuntary?
to provide support & VOLUNTARY movement of the body
what is the function of cardiac muscle? is it voluntary or involuntary?
to pump blood INVOLUNTARILY - only found in the heart
what is the function of smooth muscle? is it voluntary or involuntary?
to move the contents of the body [intestines, blood] & control passages such as sphincters - INVOLUNTARY
what is the structure of nervous tissue?
-nervous tissue = neurons, which have one cell body which branches off into many processes
what is the function of nervous tissue?
to receive information, integrate information, and send signals to other neurons or muscles
what is a regulator?
an animal that maintains its internal conditions regardless of external conditions - such as mammals with body temp
what is a conformer?
an animal whose internal conditions vary based on the external conditions - such as fish with body temp
what is homeostasis?
the ability to maintain conditions in the body in dynamic equilibrium based on an ideal “set point”
what is negative feedback?
a mechanism of returning to homeostasis by creating changes that oppose the initial stimulus (ex - if body temp gets too low, negative feedback works to bring it back up)
what are the four components of a negative feedback system?
- stimulus
- receptor / sensor
- control center
- effectors
what is the “stimulus” component of the negative feedback system?
a physiological variable that can be measured / “recorded” in the body. such as a low body temp
what is the “sensor” component of the negative feedback system?
a specialized receptor that can sense a stimulus. such as thermoreceptors for body temp
what is the “control center” component of the negative feedback system?
a “center” [usually the brain] that integrates receptor info and sends out effectors to actualize the change. such as the hypothalamus regulating body temp
what is the “effector” component of the negative feedback system?
an action that is carried out to reverse the initial negative feedback stimulus. such as shivering/moving to increase body temp
what is positive feedback?
when a stimulus received by the body results in an amplified version of that stimulus. think blood clotting / pregnancy
what is thermoregulation?
the process by which animals maintain their body temp within a tolerable range
what are endotherms?
animals that obtain heat from their metabolism [the INSIDE], such as mammals
what are ectotherms?
animals that obtain heat from their surroundings [the OUTSIDE], such as reptiles
what is bioenergetics?
the study of energy flow through an animal
what is metabolic rate?
the sum of all energy requirements of an animal over a period of time
what is the basal metabolic rate?
the minimum energy required for an endotherm at optimum temperature, typically a big number
what are the units of measurement for metabolic rate?
kilocalorie (kcal) or joule (J / kJ)
what is the standard metabolic rate?
the minimum energy required for an ectotherm, which varies with temperature
why do ectotherms have a much less demanding metabolic rate than endotherms?
they don’t need to spend energy to keep themselves warm; their environment does it for them
how does size influence metabolic rate in terms of calories per day?
metabolic rate / energy intake is DIRECTLY PROPORTIONAL to body mass. large animals need more energy than small ones
how does size influence metabolic rate in terms of gram per body mass?
metabolic rate per gram of body mass is INVERSELY proportional to body mass. small animals have higher metabolic rates per gram of body mass than big ones
why do smaller animals have a higher metabolic rate (gram per body mass) than larger animals?
small animals have a higher surface area - volume ratio, meaning they lose heat faster
