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Flashcards in excretory system Deck (53)
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1

– medial side
-where renal artery and nerve enter kidney
-where renal vein, ureter, lymphatic vessels exit kidney
-opens into the renal sinus

hilum

2

contains blood vessels
-part of the system for collecting urine and adipose tissue

renal sinus

3

– cone-shaped
-tip project toward the center

Renal Pyramids

4

surrounds tip of renal pyramid
-calyces join to form renal pelvis

Calyx –

5

functional unit of each kidney
-approx. 1.3 M for each kidney

nephron

6

enlarged end of nephron, double-walled chamber

bowman's capsul

7

tuft of capillaries (ball of yarn)

glomerulus

8

carry fluid from cortex through medulla

Collecting ducts –

9

– (15%) have loops of Henle that extend deep into the medulla

Juxtamedullary nephrons

10

(85%) loops of Henle do not extend deep into the medulla

Cortical nephrons –

11

parts of filtration membrane


 Endothelium of glomerular capillaries
 Podocytes
 Basement membrane

12

Structures consisting of Simple cuboidal epithelium

 Proximal convoluted tubules
 Thick segments of Loop of Henle
 Collecting ducts

13

consists of microvilli and mitochondria that actively transport ion & molecules across the wall of nephron

Simple Cuboidal epithelium –

14

Structures consisting of Simple Squamous

 Thin segments of the descending and ascending loop of henle

15

– formed when the distal convoluted tubule come in contact with afferent arteriole
-certain cells secrete renin

Juxtaglomerular apparatus

16

movement of water, ions and small molecules through filtration membrane into Bowman’s capsule

A.FILTRATION –

17

portion of plasma entering the nephron
-formation depends on filtration pressure (pressure gradient)

Filtrate -

18

– blood pressure in the glomerular capillary

Glomerular capillary pressure

19

– pressure of the filtrate already inside Bowman


Capsular Pressure

20

– pressure within glomerular capillary
-Because most plasma proteins do not pass the filtration membrane, they produce an osmotic pressure that favors fluid movement into the glomerular capillary from Bowman’s capsule


Colloid Osmotic Pressure

21

– allows small solutes and water to readily pass but not blood cells and most proteins except for albumin
-thus filtrate contains no cells and little protein (albumin)

Filtration membrane

22

– movement of substances from filtrate across nephron wall back into the blood of peritubular capillaries

TUBULAR REABSORPTION

23

active transport of solutes across nephron walls into the filtrate
-can either be active or passive


C. TUBULAR SECRETION –

24

– secreted by cells of juxtaglomerular apparatuses in kidneys
-acts on angiotensinogen to convert it into angiotensin I
-angiotensin-converting enzyme converts angiotensin I into angiotensin II

renin

25

– acts on the adrenal cortex, causing it to secrete aldosterone

angiotensin II

26

– increases rate of active transport of Na in distal convoluted tubules and collecting ducts

Aldosterone

27

– secreted by posterior pituitary gland
-passes through circulatory system to the kidneys
-regulates amount of water reabsorbed by the distal convoluted tubules and collecting ducts
-release is regulated by hypothalamus
-also influenced by baroreceptors (monitor BP) ↓BP, ↑ADH secretion

ADH

28

– secreted from cardiac muscle cells in the right atrium of the heart

C. ATRIAL NATRIURETIC HORMONE

29

– small tubes that carry urine from renal pelvis of kidney to posterior inferior portion of urinary bladder
-transitional epithelium

Ureters

30

hollow, muscular container in the pelvic cavity posterior to pubic symphysis
-stores urine, thus its size depends on the quantity of urine present

ub

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