practical lab 3

Question 1

endoderm

Answer 1

inner most layer, lines the primitive gut, and gives rise to the lining of the digestive tract and its out-pocketing such as liver and lungs and vertebraes

Question 2

which layer forms most of the muscles and organs between the gut and the outer covering of the animals

Answer 2

mesoderm

Question 3

body plan of flatworms (Platyhelminthes)

Answer 3

acoelomate body
No cavity between the digestive tract and the other body
Smiplest body form

Question 4

body plan of round worms

Answer 4

pseudocoelomate body plan

it has a fluid filled cavity called as the pseudocoelom. located between the digestive tract and the outer body.

layer of mesoderm under the outer body wall.

tube within a tube body plan

Question 5

body organizational level seen in the annelids

Answer 5

coelomate body plan

have a body cavity known as the coelom , that is completely lined by the mesoderm

Question 6

round worms

Answer 6

Phylum nematoda
example - ascaris

Question 7

Differtiating feature in males for ascaris

Answer 7

At the posterior end males have COPULATORY SPICULE i.e. hook

Question 8

How are eggs produced in ascaris

Answer 8

meiosis within the ovaries

Question 9

what is the function of copulatory spicule

Answer 9

Holding the female’s genital pore open

Question 10

Function of cloaca in ascaris

Answer 10

1. found at the prosterior end of the intestine and is connected to the anus
2. collecting area for fecal matter from the intestine and sperms from the seminal vesicle

Question 11

Type of sperm in ascaris

Answer 11

amoeboid and not flagellated

Question 12

Segmented worms

Answer 12

Phylum annelida

earthworms and clam worms

Question 13

metamerism

Answer 13

body segmentation on the phylum annelida

Question 14

clitellum? and its function

Answer 14

saddle like swelling on the dorsal surface of the earth worm

1. produces a mucus sheath for mating
2. cocoon formation within which the fertilized eggs are deposited

Question 15

circulatory system in earthworms/phylum annelida

Answer 15

closed circulatory system

Question 16

Eating pattern in earthworms

Answer 16

They are foraging herbivorous annelidas

Question 17

Steps for food ingestion in earthworms

Answer 17

pharynx -> esophagus -> stored in the crop -> gizzard -> large intestine for digestion and absorption

Question 18

What is the function of typhlosole (in earthworms)

Answer 18

increases the surface area for absorption

Question 19

Excretory organs in earthworms

Answer 19

Nephridia

Question 20

how is internal transportation done in phylum annelids

Answer 20

It is performed by coelomic fluid

Question 21

How does reproduction occur in earthworms

Answer 21

mating by attachment of CLITELLA

Question 22

seminal receptacles

Answer 22

bulb like organ which receives sperm from another worm and the sperm received is stored here.

Question 23

What are parapodia? (usually in clam worms)

Answer 23

They are fleshy paddle like appendages that may be used for either crawling or swimming

They have a large surface area for gaseous exchange as they are rich with blood vessels

Question 24

Reproductive organs in clam worms

Answer 24

Nereis

Question 25

Feeding habits of the clam worm

Answer 25

carnivorous in nature

Question 26

phylum arthropoda

Answer 26

crayfishes and grasshoppers

Question 27

What are the reasons for the tremendous biological success of the phylum arthropoda?

Answer 27

1. external exo skeleton 2. joined appendages

Question 28

Where are crayfishes usually found

Answer 28

found in aquatic environments with adequate amounts of Ca salts

Question 29

What protects crayfishes from predators?

Answer 29

chintinous exo skeleton

Question 30

Differing feature in males and females (externally) in crayfishes.

Answer 30

both male and female have the same number of appendages males have modified first 2 fair of appendages known as swimmeretes

Question 31

what is the function of swimmertes in crayfishes?

Answer 31

found in males they are elongated and can come together to form a trough like channel to transfer the sperm

Question 32

Division of the body of the crayfish

Answer 32

the cephalothorax and the abdomen

Question 33

what is the function of the digestive glads in the crayfishes?

Answer 33

they are located at the posterior part of the cephalothorax and these glands secrete enzymes and also store food.

Question 34

ingestion/digestion of food in crayfishes

Answer 34

mouth -> short esophagus-> large stomach which contain the gastric mill which are used to grind food -> intestine -> ends at anus

Question 35

the osmoregulatory and excretory organ in crayfishes.

Answer 35

green glands (they are actually pinkish in color)

Question 36

respiratory system in crayfishes

Answer 36

gills, they are highly vasucalireized for gaseous exchange.

Question 37

ostia

Answer 37

small holes in the heart of the crayfishes from which the blood renters the heart

Question 38

The division of the body of a grasshopper

Answer 38

1. head 2. thorax 3. abdomen

Question 39

how can you tell apart the 2 sexes of a grasshopper

Answer 39

the female has ovipositor - > modified terminal segments in the females to lay and position eggs

Question 40

What are the terminal segments in a grasshopper

Answer 40

the terminal segments bear the reproductive genital

Question 41

ingestion and digestion in a grasshopper

Answer 41

pharynx -> esophagus -> crop (where the food is stored) -> stomach -> attached to gastric caecae -> intestine -> rectum -> anus

Question 42

what is the function of the gastric caecae

Answer 42

it is six doubled finger shaped digestive gland which produce enzymes which are secreted into the stomach which aid in digestion

Question 43

what are the malphigian tubules

Answer 43

the perform the function of excretion and osmoregulation they are rich with blood wastes would enter the tube and are removed via the HINDGUT

Question 44

what are the testes composed of in case of grasshoppers

Answer 44

they are composed of follicles

Question 45

what are the ovaries composed of in the case of grasshoppers

Answer 45

they are composed of several tapering egg tubes