Biology: Biomolecules, Cells, and Organ Systems Flashcards Preview

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Flashcards in Biology: Biomolecules, Cells, and Organ Systems Deck (32):
1

Glycogen-Lactic acid system

Involves

1- the convesion of muscle's: glycogen  ► glucose

and 

2- (aeorobic) glucose  ► lactic acid

Once lactic acid is formed in muscles cells, it diffuses out into blood stream and intestitial fluid (IF).

 

2

Infection and sedimentation rate

Most acute generalized infections and some local infections raise the rate of sedimentation. A raised sedimentation rate may be among the first signs of an otherwise hidden disease.

3

Aldostrone and urine tonicity

Aldostrone indirectly regulates urine tonicity by controlling the Na+ levels in ascending limb of the loop of Henly. 

4

Second phase of hematocrit procedure

Hint- centrifugation

In the second phase of the procedure, the tube is centrifuged so that its contents separate into three layers

1- packed red blood cells (RBC's- erythrocytes) at the bottom.

2- a reddish gray layer of white blood cells (WBC's -leukocytes) and platelets in the middle.

3- Plasma at the top. The hematocrit is expressed as the percentage of the total blood volume occupied by the packed red blood cells.

5

Two sources of generating pressure gradient in circulatory system and their impact on the net movement of fluid with respect to vessels:

1- hydrostatic- generated by the heart

Pushed the fluid out of the vessels.

2- oncotic- created by and depends on the total number of plasma particles

Draws the fluid into the vessels.

6

Heart beat initiation and regulation

Heart beat is initiated by SA node and regulated (not controlled) by the accelarator and vagus nerves.

7

Selective B-cell X-linked genetic disease 

The diffense that might remain intact or change as a result

Burton's Agammaglobulinemia

B-cells are absent in male infants. Child becomes ill at 8-9 months of age ( when deprived of mother's passive immunity).

It's indicated by the absence of circulating Ab's.

Recurrent bacterial infection

Defense ag. virus and fungi is intact.

8

Purpose of TCA

Generating high energy intermediates which can be used for ATP production.

9

A mutation that dosn't involve a change in the base sequence of DNA.

Non-disjunction (faliure to seperate)

10

How many ATP molecules are produces from the oxidation of 2 molecules of glucose, as a result of substrate-level phosphorylation only?

 

 

Substrate-level phosphorylation: ATP synthesis directly linked/ coupled with glucose degradation, without participation of any intermediates such as NAD+.

For each molecule of glucose:

2 ATP (Glycolysis) + 1 Net ATP(TCA)

Therefore: 2 x (3)

* THE ANSWER MUST BE VERIFIED

11

Net number of ATP (molecule/1 glucose) produced bu an obligate anaerobe

2 net ATP

 

Only glycolysis and fermentation are present in obligate anaerobes

Obligate aeorobe, on the other hand, produces 36-38 molecules of ATP per one molecule of glucose.

12

Two types of chromosomal non-disjucnction and their corresponding phase

Homolog chromosomes- meiosis I

Sister chromatids- meiosis II

13

Hormones of adrenal gland

 

  1. Glucocorticosteroid- e.g. Cortisole/ adrenal cortex
  2. Mineralocorticoids- e.g. aldosterone/ adrenal cortex Aldostrone (indirect, Na+, ascending loop)
  3. Catecholamines- e.g. epinephrine and norepinephrine/ adrenal medula

14

Fate/removal of lactic acid during recovery

1- diffuses out of muscles cells into blood and IF.

a- lactic acid → pyruvate

b- lactic acid → glucose (liver) → glycogen ( replenish depleted glycogen of the muscle cells).

 

Note: part of muscle's glycogen-lactic acid system

15

Selective T-Cell disease

The diffense that might remain intact or change as a result

DiGeorge's Syndrome

Due to underdevelopment or absence of thymus

Normal cirulatin Ab's. However, impaired defense ag. viral and fungal infections.

 

Note: This syndrome along with Burton's agammaglobulinemea are ideal case to distinguish between the functioning of B and T cells.

16

Natural passive immunity

1- Transfer of Abs through placenta

2- Administration of RhoGAM to Rh- female- Goal: to prevent sensitization against the Rh+ fetus.

 

Note: Passive immunity is transient since only Ab's and not the B cells have been transfered.

17

The layer of hematocrit with the potential to indicate the presence of hemophilia.

Hint: sex-linked genetic disorder with dificiency/abnormality in clotting factors.

Layer 3- to layer, plasma otherwise known as the liquid portion of blood.

18

Mutations that result in non-functional proteins

frameshift and non-sense

19

Functions of Placenta

1- Secretion - HCG

2- Absorption- Nutrients from maternal blood spc. during the first half of pregnancy.

3- Excretion of CO2

Note: Placenta dosn't protect against toxins since it is permeable.

20

Hematocrit and sedimentation rate

During phase 1- The tube is allowed to stand for one hour, after which the sedimentation rate (how rapidly blood cells settle out from plasma ) is determined.

21

Explain how the depth of each layer of hematocrit is affected in the following diseases/conditions:

Polycythemia

iron-deficiency anemia

leukemia

jaundice

The red blood cell layer is abnormally thick in the disease polycythemia and too thin in iron-deficiency anemia;

white blood cells are too abundant in leukemia; and plasma is deep yellow in jaundice (often caused by liver disease).

22

coenzyme

organic (less involved), carriers NADH

Vitamins are great examples of coenzymes.

B3→ NAD+

B5 →CoA

Organics can be both coenzymes and cofactors

23

cofactor

minerals ( more involved)

Mg2+in DNA Pol.

 

24

Name an oxidoreductase that requires NADH as a coenzyme.

Lactate dehydrogenase

Pyruvate + NADH ⇔ Lactic acid + NAD+

25

An enzyme that transfers functional groups

transferase

26

An enzyme that joins two molecule

ligase

27

An enzyme that moves electrons

oxidoreductase

e.g. lactate dehydrogenase

28

An enzyme that forms isomers, with an example

Isomerase

e.g. phospoho-gluco isomerase

G6P → F6P

29

An enzyme that breaks bonds with H2O.

With example- Hint: Proteins.

hydrolase

Commonly seen in hydrolysis rxn of peptide bonds.

Lys-Ala + H2O → Lys + Ala

e.g. Serine hydrolase

30

An enzyme that breaks bonds WITHOUT H2O (Not a hydrolase) and/or via oxidation-reduction (Not an oxidoreductase).

With example- Hint: Urea Cycle

lyase

Arginosuccinate → Arg + Succinate

E: arrginosuccinate lyase

31

Four general categorization of enzymes:

1- transfer proton (Acid/Base): enol-keto tautomerization

2- transfer electron- Decarboxylation

3- Charge stabilization- Po3 2- stabalized by the Mg2+ of DNA POL.

4- Inc. freq. of appropriate collisions.

32

Polycythemia

Abnormal RBC's production by the bone marrow (BM).