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Flashcards in Biology Deck (27):
1

What is connective tissue?

Provide support/framework for epithelial cells; blood, bone, cartilage, tendons, ligaments, adipose tissues

2

What are the three main parts of Darwin's Theory of natural selection?

1. Organisms produce offspring of few survive. Chance variations within populations are heritable.
2. If the variation increases an organism's survival chances, the variation is termed favorable.
3. These individuals will have greater fitness (reproductive success) and fitness is directly correlated to organism's genetic contribution to the next generation.

3

What are the layers of the skin?

Epidermis, dermis, hypodermis

4

What are the layers of the epidermis?

Corneum (dead skin cells, protection
Lucidum (thick, hairless, hells of palms)
Granulosum (keratonocytes die)
Spinosum (langerhancells, macrophages, present antigens to T- cells)
Basale (stem cells=> keratinocytes; melanocytes --> skin color)

5

What are the layers of the dermis?

Papillary- loose connectice tissue
Reticular- hair follicles, sweat glands, blood vessels

6

What does the hypodermis contain?

Fat = connective tissue

7

What are the sensory receptors of dermis?

Merkel- deep pressure + tecture
Pacinian- deep pressure + vibration
Meissner's - light touch
Ruffini- stretch

8

Where is the electron transport chain located in prokaryotes?

Plasma membrane

9

What is the molecular weight of an amino acid?

110 Da

10

What is commensalism?

one benefits; the other doesn't but doesn't harmed either

11

What is mutualism?

mutually dependent

12

What is parasitism?

one benefits; the other is harmed

13

What is senescence?

biological aging in which cells no longer replicate (shortened telomeres)

14

What does the ectoderm form?

epidermis, NS, adrenal medulla

15

What does the mesoderm form?

dermis, musculoskeletal system, circulatory system, adrenal cortex

16

What does the endoderm form?

epithelial lining of GI and resp systems

17

What is induction?

The release of factors that promote differentiation in other tissues (can be reciprocal)

18

What cells produce myelin in the CNS?

oligodendrocytes

19

What cells produce myelin in the ONS?

Shwann cells

20

upstream and downstream a gene

upstream is before the gene; downstream is after the gene

21

osteoblast

bone-forming cells (build)

22

osteoclasts

bone-resorbing cells (breakdown)

23

vasoconstriction

increases blood pressure but decreases oxygen delivery to those tissues

24

perfusion

the movement of fluid through the circulatory or lymphatic system, specifically the delivery of blood to capillary beds in tissues

25

Myosins

hydrolyze ATP to power sarcomere contract

26

Kinesins and Dyneins

motor proteins involved in intracellular transport; deliver vesicles along MT's (kinesins towards + and dyneins toward - )

27

Eukaryotic cell membranes only have fatty acids with

1) and even number of Carbons
2) only CIS double bonds (NO TRANS AT ALL)