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Flashcards in Chapter 2 Deck (43)
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1

Matter

- anything that takes up space and has mass
- made up of elements
- consists of chemical elements in pure form and in combinations called compounds

2

Elements

substances that cannot be broken down to other substances by chemical reactions

3

Structure

helps dictate the function

4

Compound

- a substance consisting of two or more elements combined in a fixed ratio
- has characteristics different from those of its elements

5

Calcium and life

-associates with calmodulin
1) bones
2) muscle contraction
3) RBC development
4) brain function --> learning and memory

6

What four elements make up 96% of living matter?
-plus calcium

1) Oxygen (65%)
2) Carbon (18.5%)
3) Hydrogen (9.5%)
4) Nitrogen (3.3%)
Calcium (1.5%)
-about 25 of 92 elements are essential to life

7

Hyperthyroidism
(goiter)
(thyroid growth)

-Thyroid produces Thyroxine hormone (T3 and T4) from iodine
-iodine deficiency causes the brain to secrete thyroid stimulating hormone (TSH)
-TSH will cause the thyroid gland to grow and secrete (more) hormones
-normally T3 and T4 will give negative feedback and tell the pituitary gland to slow down the production of TSH
-can cause vision problems, heart attack

8

Pituitary Gland --> Thyroid --> Thyroxines (T3 and T4) --> growth, metabolism, body temp, vision, bone formation

- pituitary gland produces TSH
- Thyroid gland needs iodine to produce T3 and T4
- sometimes thyroid hormone is given to help

9

an element's properties depend on the...

- structure of its atoms

- each element consists of a certain kind of atom that is different from those of other elements

10

Atom

the smallest unit of matter that still retains the properties of an element and are composed of even smaller parts called subatomic particles

11

Subatomic Particles

Neutrons, Electrons, Protons

12

Neutrons

- subatomic particle that has no electrical charge
- found in the atomic nucleus

13

Electrons

- subatomic particle that is negatively charged
- surround the nucleus in a "cloud"

14

Protons

- subatomic particle that is positively charged
- found in the atomic nucleus

15

Atomic Number of an element

the number of protons and is unique to each element

- Atoms of the various elements may occur in different 1) forms and differ in 2) their number of subatomic particles.

16

an atom's electrons ...

vary in the amount of (potential) energy they possess

17

Energy

the capacity to do work

18

Potential Energy

energy that matter possesses because of its location or structure

19

Valence electrons

electrons in the outermost shell, or valance shell, and determine most of the chemical behavior of an atom

20

Covalent Bond

- sharing of a pair of valence electrons with two elements and form a molecule
- polar and non polar

- i.e. water (H2O), methane (CH4)

21

the formation and function of molecules depend on ...

chemical bonding between atoms

22

Molecules

consists of 2 or more atoms held together by covalent bonds

23

Single bond

sharing of one pair of valence electrons

24

Double bond

sharing of two pairs of valence electrons

25

Polar covalent bond

the atoms have differing electronegativities (attraction for the shared electrons)
- share the electrons unequally ("hogs" all the electrons/energy)
- i.e. water

26

Ionic bond

- atoms strip electrons away from their bonding partners
- electron transfer between two atoms create ions

27

Ions

charged atoms

28

Anion

negatively charged ion

29

Cation

positively charged ion

30

Nonpolar

- don't dissolve in water very well
- usually hydrophobic