Correct Answer: C) Proximal Convoluted Tubule

Explanation

Glucose is a type of sugar that is important for providing energy to the body's cells. However, when there is too much glucose in the blood, the kidney has to filter it out and excrete it in the urine. In the process of filtering the blood, some important substances like glucose are also removed from the blood, but the body needs to reabsorb them to avoid losing them completely. The kidney is made up of different structures that perform different functions. One of these structures is the proximal convoluted tubule. This tubule is responsible for reabsorbing many important substances, including glucose, from the filtered fluid before it is excreted as urine. Therefore, the correct answer to the question is option C: Proximal Convoluted Tubule. Bowman's capsule, on the other hand, is a structure in the kidney that forms part of the filtration unit. It is responsible for filtering the blood to form urine, but it does not reabsorb glucose. The loop of Henle and distal convoluted tubule are also structures in the kidney, but they are not primarily responsible for the reabsorption of glucose. In summary, glucose is reabsorbed in the kidney mainly by the proximal convoluted tubule, which is responsible for reabsorbing many important substances from the filtered fluid before it is excreted as urine.

Correct Answer: D. homeostasis

Explanation

The ability of organisms to maintain a constant internal environment is known as homeostasis. Homeostasis is a fundamental biological concept that refers to the ability of living organisms to maintain a stable and relatively constant internal environment despite changes in the external environment.

Correct Answer: C. lung fish

Explanation

(a)(i) The process of osmoregulation in a named unicellular organism, e.g. Paramecium /Amoeba is as follows: Contractile vacuole carries osmoregulation in paramecium. The cell content of paramecium is hypertonic to the external medium. Therefore water enters, by osmosis into the cytoplasm and later into the contractile vacuole. To prevent the cell from being over turgid and bursting, the contractile vacuole discharges its content from time to time, thereby maintaining water balance within the organism.

(ii) The process of osmoregulation in man begins with the kidney. The kidneys carry out osmoregulation in

man, when the osmotic concentration of blood is higher than that of the cell content, by means of sugar/ Nucleus mineral salts/amino Acids/other plasma solutes. The kidneys extract these substances from the blood/ body cells and absorb more water. When these substances are present in small amounts in the blood there is higher osmotic pressure in body cells, thus decreasing osmotic concentration of the blood. The kidney extracts more water than usual by the action of ADH/hormones and more concentrated urine is produced, thus keeping the osmotic concentrations of blood and cell fairly constant/avoiding any damage. Water can also be lost through sweating and breathing out moist air.

(b) The mammalian skin can react to regulate the body temperature in a hot room. When there is excess heat in the body, blood flow in the dermal capillaries is stimulated and the blood vessels under the skin epidermic dilates whereby more blood is brought to the surface or the sweat picks up the latent heat of vaporization from the skin, cooling the skin down. Heat is also lost by radiation which allows air to flow through the follicles and through convention. The hair lies inclined / flat.

Correct Answer: D. semicircular canals

Explanation

(a) Pollination and Fertilization;

(i) Whereas pollination is the transfer of pollen grains from the anther of a flower to the stigma of a flower; fertilization is the fusion of the male gamete/nucleus, with that of the female gamete/nucleus; to form a zygote

(ii) Pollination precedes fertilization

(b) Features that ensure cross pollination and Examples;

(i) Dioecious plants/male and female flowers occur on separate plants e.g. pawpaw/ any correct example.

(ii) Dichogamy/Male and female parts mature at different times

(iii) Phragmanthera/ mistletoe; is protogynous/protandry/carpels mature before Stamens (thus separating. the reproductive structure in time) sun flower/cotton is protandrous/ stamen, mature before carpel. Crotolaria examples of ptologynous plant. Male and female parts are of different lengths/heterostyly/long style and short stamen e.g. Morinda. Moneocious plants/Male and female flowers occur on the same plant in different position e.g. Maize/Luffa/Oil palm/coconut etc (male flower at the apex matures first whereas the female flower in the axil of leaves matures later) the feathery stigma hang loosely and can catch airborne pollen grains but not from the same flower.

Structure: Most flowers are so structured as to prevent self pollination since only a particular insect/animal can effect pollination; e.g. Crotalaria/CentrocemaNigna/pea/groundnut- stamens mature first shedding pollen into a sac-like tube formed by the keel honey guides on the standard which direct the bee to the sectaries and the stigma points towards entrance of keel and can only receive pollen brought in by a visiting bee. Self-incompatibility/self-sterility (certain chemicals on the surface of the stigma prevent growth in pollen tubes; of pollen grains from the same flower) e.g. Clover. Possession of brightly coloured petals attract insects e.g. Delonix, Hibiscus. Sweet smell for attraction of insects e.g. Rose flower.

(c)(i) Agents of pollination are as follows

(a) Insect/bat/animal/any named animal

(b) Wind/Air

(c) Water

(ii) Features of wind dispersed fruits/ seeds

(a) Seeds are almost always with floss thereby aiding its ability to be flown or be airborne.

(b) Winged seeds/fruits

(c) Light-weight seeds/fruits

(d) Parachute/hairs.

Correct Answer: B. a mammal

Correct Answer: A) homeostasis

Explanation

The question is asking about the term used to describe the process of maintaining a constant internal environment of an organism. This process is known as homeostasis. Homeostasis involves the regulation of various physiological variables such as body temperature, pH levels, and blood sugar levels within a narrow range in order to maintain optimal conditions for the body's cells to function properly. Option A, homeostasis, is the correct answer to the question. Option B, hemorhesis, is not a term used in Biology. Option C, turgidity, refers to the state of being swollen or distended due to high fluid content and is not directly related to maintaining a constant internal environment. Option D, homolothermy, refers to the ability of an animal to maintain a constant body temperature, which is related to homeostasis but not the same thing. Option E, dieresis, refers to the increased production of urine by the kidneys and is not directly related to maintaining a constant internal environment. It is important for organisms to maintain homeostasis as it allows them to function properly and respond to changes in their environment. Examples of homeostatic mechanisms include sweating to regulate body temperature, insulin production to regulate blood sugar levels, and the release of hormones to regulate various physiological processes. Overall, the correct answer to the question is Option A, homeostasis.

Correct Answer: A. parasitism

Explanation

Cows are not immune to ticks and thanks to their hairy hides, ticks love to attack herds of cattle. Feeding off their host's blood supply, ticks spend their lives on animals of all kinds, including cows. Ticks can even transmit potentially fatal diseases to cows through their bites. The cattle tick is considered to be the most important parasite of livestock worldwide

Correct Answer: C. the stomata and lenticel only