Test One Flashcards
(75 cards)
What is a tissue?
similar cells performing a common function
Neurons/Nervous Tissue (examples & purpose)
Ex: motor neurons, cortical interneurons
Purpose: communication; sending and receiving information
Muscle Cells/Tissue (examples, purpose, voluntary?
Ex: cardiac myocytes, skeletal muscles, smooth muscle
Purpose: contract and generate movement
Atrophy: muscles haven’t contracted in a while and die
Epithelial Cells/Tissue (purpose, where?)
Purpose: exchange and boundaries; lines all body cavities e.g., mouth, nose, ears
Where: makes up most skin; all glands made of this
Epithelial Cells/Tissue (purpose, where?)
Purpose: exchange and boundaries; lines all body cavities e.g., mouth, nose, ears
Where: makes up most skin; all glands are made of this
Connective Tissue (characterized? & examples)
Characterized by: have few cells, lots of extracellular materials (water, salts & proteins), and are diverse
Ex: blood, fat, ligaments, tendons, cartilage & bone
Endocrine Gland
secretes molecules (hormones) into the bloodstream a.k.a. capillaries
Exocrine Glands
uses a DUCT to secrete molecules into a body cavity or exterior body (sweat, saliva)
Homeostasis (what & how)
The body’s ability to maintain a stable (not constant internal environment despite changes in the external environment.
Accomplished through negative feedback and antagonistic effectors
Negative Feedback (what & example)
What: returning conditions to a “set point” and input and output are opposites!
Ex: Sweat when hot. Sweat evaporates and you cool.
Why do you shiver when with a fever?
- Involved in changing the body temp set point (hypothalamus)
- shiver to make fever happen and beat the infection
- you feel cold bc set point had changed to 103
- once infection is defeated, hypothalamus returns set point
- sweat to cool down
Positive Feedback (what & examples)
What: moves conditions AWAY from “set point”/normal conditions. input and output are the same.
Ex:
- Contractions cause oxytocin to be released, causing more contractions. Baby’s head against the cervix activates stretch receptors that signal the hypothalamus to release more oxytocin and cause stronger contractions.
- Scratch a bug bite, which releases histamine, causing it to itch more. Input itching, output itching.
Ionic Bond
between - and + charge
Covalent Bond
two atoms SHARE electrons
Nonpolar Covalent Bond
electrons shared equally, neither will have a charge
Polar Covalent Bond (strong)
electrons go to atom with more protons, shared unequally
Hydrogen Bond
the partial positive charge in a polar covalent bond H2O is attracted to the partial negative charge in the O of H2O
Why don’t water and oil mix?
Oil is made of a lot of nonpolar bonds with no charge. To dissolve in water, it must form hydrogen bonds, but this cannot happen without a charge.
Electronegativity
an atom’s ability to attract and hold electrons; a measure of how + a nucleus is
HCNO*
next to = nonpolar
separated = polar
Monosaccharides (carb)
CHO in a 1:2:1 ratio, ring structure
major purpose: short-term energy
Disaccharides (carb)
2 sugars
Polysaccharides (carb)
hundreds, thousands of monosaccharides
-GLYCOGEN! the energy storage molecule, used for quick energy, metabolized when sugar levels drop
-body does not store glucose well, so when levels are high, glycogen is assembles and stored in muscles and liver
Carb-loading
increasing the amount of glycogen stored in the body prior to a competition
Water Weight/Burning Energy
Body burns through energy blood sugar –> glycogen (w/polar water) –> fat (nonpolar, no water)