1. The anatomy of plant organs makes them incredibly efficient structures for ca

ID: 81204 • Letter: 1

Question

1. The anatomy of plant organs makes them incredibly efficient structures for carrying out processes like photosynthesis and nutrient absorption. Describe and explain at least five ways in which leaves or roots optimize the conditions for photosynthesis or nutrient absorption, respectively.

2. Explain how the innate immune system compares to the adaptive immune system of vertebrates?

3. Organisms which posses open and closed circulatory systems differ not only in their transport but also in their method of gas exchange. Compare open and closed circulatory systems in terms of their transport and in terms of their associated gas exchange systems.

4. Imagine a hummingbird species has detected the odor of nectar. Explain how the signal is received and then transmitted from one neuron to the next. In your explanation diagram the stages of an action potential and indicate what initiates the action potential

5. Explain how LH, FSH, estradiol, and progesterone act to control follicle maturation, ovulation, and endometrium maintenance.

Explanation / Answer

Adaptation of leaves

purpose

Surface area of leaf is large

To absorb more light

Presence of stomata

Carbon dioxide diffuses through stomata into leaf

Chlorophyll

Photosynthesis machinery

Epidermis is thin

Distance travelled by carbon dioxide into leaf cell reduced and light also reaches to the palisade cells

Cuticle is thin and made up of wax

Protects the leaf but do not block the light

Adaptation of roots

Presence of Root hair cells

Presence of carrier molecules on root hair cell membranes

Root hair cells have large surface area

Inside the root cells, concentration of minerals is higher as compare to the soil which results into root pressure. This resulted in force of uptake of water and minerals from the root through the xylem.It also resulted in guttation

Nutrients can also be absorbed by both the systems: active as well as passive transport

Innate

Adaptive

Specificity

Non-specific

Highly specific

Action

For structures shared by a group of microbes

For special antigens of microbial and non-microbial agents

Used against

For microbes

Microbes and non-microbial substances called antigens

Memory

No memory

Long term memory

Effective immediately after exposure

acts within minutes

requires several days before becoming effective

Diversity

Limited

High

Potency

Less

Line of defense

1st line as intrinsically present

Develops after exposure

Speed

Faster response

Slower response

Complement system activation

Via alternative and lectin pathways

Activated by classical pathway

Components

1. Cells

Phagocytes

2. Blood proteins

Complement

Antibodies

Anatomic and physiological barriers

Open Circulatory System

Closed Circulatory System

Blood is in direct contact with body tissues.

Blood always flows in blood vessels i.e. arteries, capillaries and veins

There are no blood vessels. Haemolymph flows in sinuses (hoemocoel)

There is a system of arteries, capillaries and veins through which blood flows and exchange of gases takes place between tissues and blood.

This system can't maintain blood pressure and no respiratory pigment present

Blood Pressure can be maintained. Haemoglobin (respiratory pigment) present in blood.

When blood is in direct contact with tissues, only then exchange of materials takes place

Through capillaries, nutrients and waste materials are exchanged between tissues and blood by means of tissue fluid.

It doesn’t support transport of gases but by the tracheal system.

Gases and nutrients are transported

requires less energy for distributing blood

More energy for distributing blood

Eg. molluscs and arhthropods

Eg. Humans

follicle maturation : LH And FSH works together i.e. synergistically for the normal growth and maturation of follicle. Both the hormones are complementary to each other.

Ovulation: FSH stimulates the follicle i.e. growth of the egg and also act as trigger for the release of estrogen in the system. Once estrogen is released, FSH level will reduce and LH will increase which is responsible for ovulation

Estradiol: In females, it acts as a growth hormone for the reproductive organs like the vagina, the fallopian tubes, the endometrium etc. It is responsible for enhancing growth of the endometrium. It is also responsible in maintaining oocytes and is a kind of trigger to lead a series of events which finally resulted in ovulation.

Progesterone rises during the latter half of the menstrual cycle. Its function is to thickening and maintaining of the endometrium lining of the uterus so that uterus can receive and nourishes the fertilized egg.